feat: add notifications and project shares features

- Backend: notifications + shares routes, DB tables, SqliteAdapter methods
- Frontend: NotificationPanel (bell icon + dropdown), ShareDialog, Dashboard integration
- Styles: notification + share dialog CSS

frontend/src/components/NotificationPanel.tsx

@@ -0,0 +1,103 @@
+/**
+ * NotificationPanel – Shows user notifications with mark-read and delete
+ */
+import { useState, useEffect, useCallback } from 'react';
+import { getNotifications, markNotificationRead, deleteNotification, type NotificationItem } from '../services/api';
+
+interface NotificationPanelProps {
+  token: string;
+}
+
+export function NotificationPanel({ token }: NotificationPanelProps) {
+  const [notifications, setNotifications] = useState<NotificationItem[]>([]);
+  const [open, setOpen] = useState(false);
+  const [loading, setLoading] = useState(false);
+
+  const fetchNotifications = useCallback(async () => {
+    setLoading(true);
+    try {
+      const data = await getNotifications(token);
+      setNotifications(data);
+    } catch {
+      // ignore
+    } finally {
+      setLoading(false);
+    }
+  }, [token]);
+
+  useEffect(() => {
+    if (open) fetchNotifications();
+  }, [open, fetchNotifications]);
+
+  const unreadCount = notifications.filter(n => !n.read).length;
+
+  const handleMarkRead = async (id: string) => {
+    try {
+      await markNotificationRead(token, id);
+      setNotifications(prev => prev.map(n => n.id === id ? { ...n, read: 1 } : n));
+    } catch {
+      // ignore
+    }
+  };
+
+  const handleDelete = async (id: string) => {
+    try {
+      await deleteNotification(token, id);
+      setNotifications(prev => prev.filter(n => n.id !== id));
+    } catch {
+      // ignore
+    }
+  };
+
+  return (
+    <div className="notification-panel-wrapper">
+      <button
+        className="notification-bell-btn"
+        onClick={() => setOpen(!open)}
+        title="Benachrichtigungen"
+      >
+        <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
+          <path d="M18 8A6 6 0 0 0 6 8c0 7-3 9-3 9h18s-3-2-3-9" />
+          <path d="M13.73 21a2 2 0 0 1-3.46 0" />
+        </svg>
+        {unreadCount > 0 && <span className="notification-badge">{unreadCount}</span>}
+      </button>
+      {open && (
+        <div className="notification-dropdown">
+          <div className="notification-dropdown-header">
+            <h3>Benachrichtigungen</h3>
+            <button className="notification-close" onClick={() => setOpen(false)}>×</button>
+          </div>
+          {loading ? (
+            <p className="notification-loading">Lädt…</p>
+          ) : notifications.length === 0 ? (
+            <p className="notification-empty">Keine Benachrichtigungen</p>
+          ) : (
+            <div className="notification-list">
+              {notifications.map(n => (
+                <div key={n.id} className={`notification-item ${n.read ? 'read' : 'unread'}`}>
+                  <div className="notification-item-content">
+                    <span className={`notification-type-badge type-${n.type}`}>{n.type}</span>
+                    <span className="notification-title">{n.title}</span>
+                    <span className="notification-message">{n.message}</span>
+                    <span className="notification-time">{new Date(n.created_at).toLocaleString('de-DE')}</span>
+                  </div>
+                  <div className="notification-item-actions">
+                    {!n.read && (
+                      <button className="notification-action-btn" onClick={() => handleMarkRead(n.id)} title="Als gelesen markieren">
+                        <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2"><polyline points="20 6 9 17 4 12" /></svg>
+                      </button>
+                    )}
+                    <button className="notification-action-btn delete" onClick={() => handleDelete(n.id)} title="Löschen">
+                      <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2"><line x1="18" y1="6" x2="6" y2="18" /><line x1="6" y1="6" x2="18" y2="18" /></svg>
+                    </button>
+                  </div>
+                </div>
+              ))}
+            </div>
+          )}
+        </div>
+      )}
+    </div>
+  );
+}

frontend/src/components/ShareDialog.tsx

@@ -0,0 +1,110 @@
+/**
+ * ShareDialog – Share a project with other users by email
+ */
+import { useState, useEffect, useCallback } from 'react';
+import { getProjectShares, createProjectShare, deleteProjectShare, type ProjectShare } from '../services/api';
+
+interface ShareDialogProps {
+  token: string;
+  projectId: string;
+  open: boolean;
+  onClose: () => void;
+}
+
+export function ShareDialog({ token, projectId, open, onClose }: ShareDialogProps) {
+  const [shares, setShares] = useState<ProjectShare[]>([]);
+  const [email, setEmail] = useState('');
+  const [permission, setPermission] = useState('view');
+  const [loading, setLoading] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  const fetchShares = useCallback(async () => {
+    setLoading(true);
+    try {
+      const data = await getProjectShares(token, projectId);
+      setShares(data);
+    } catch {
+      // ignore
+    } finally {
+      setLoading(false);
+    }
+  }, [token, projectId]);
+
+  useEffect(() => {
+    if (open) fetchShares();
+  }, [open, fetchShares]);
+
+  const handleShare = async () => {
+    if (!email.trim()) return;
+    setError(null);
+    try {
+      const newShare = await createProjectShare(token, projectId, {
+        shared_with_email: email.trim(),
+        permission,
+      });
+      setShares(prev => [newShare, ...prev]);
+      setEmail('');
+    } catch (err: any) {
+      setError(err.message || 'Freigabe fehlgeschlagen');
+    }
+  };
+
+  const handleDelete = async (id: string) => {
+    try {
+      await deleteProjectShare(token, id);
+      setShares(prev => prev.filter(s => s.id !== id));
+    } catch {
+      // ignore
+    }
+  };
+
+  if (!open) return null;
+
+  return (
+    <div className="share-dialog-overlay" onClick={onClose}>
+      <div className="share-dialog" onClick={e => e.stopPropagation()}>
+        <div className="share-dialog-header">
+          <h3>Projekt teilen</h3>
+          <button className="share-dialog-close" onClick={onClose}>×</button>
+        </div>
+        <div className="share-dialog-body">
+          <div className="share-form">
+            <input
+              type="email"
+              placeholder="E-Mail-Adresse"
+              value={email}
+              onChange={e => setEmail(e.target.value)}
+              className="share-email-input"
+            />
+            <select value={permission} onChange={e => setPermission(e.target.value)} className="share-permission-select">
+              <option value="view">Ansicht</option>
+              <option value="edit">Bearbeitung</option>
+              <option value="admin">Admin</option>
+            </select>
+            <button className="share-add-btn" onClick={handleShare}>Teilen</button>
+          </div>
+          {error && <p className="share-error">{error}</p>}
+          {loading ? (
+            <p className="share-loading">Lädt…</p>
+          ) : shares.length === 0 ? (
+            <p className="share-empty">Noch niemandem geteilt</p>
+          ) : (
+            <div className="share-list">
+              {shares.map(s => (
+                <div key={s.id} className="share-item">
+                  <div className="share-item-info">
+                    <span className="share-email">{s.shared_with_email}</span>
+                    <span className="share-permission-badge">{s.permission}</span>
+                  </div>
+                  <button className="share-remove-btn" onClick={() => handleDelete(s.id)} title="Freigabe entfernen">
+                    <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2"><line x1="18" y1="6" x2="6" y2="18" /><line x1="6" y1="6" x2="18" y2="18" /></svg>
+                  </button>
+                </div>
+              ))}
+            </div>
+          )}
+        </div>
+      </div>
+    </div>
+  );
+}

frontend/src/pages/Dashboard.tsx

@@ -3,6 +3,8 @@
  */
 import { useState, useEffect, useCallback } from 'react';
 import { useAuth } from '../contexts/AuthContext';
+import { NotificationPanel } from '../components/NotificationPanel';
+import { ShareDialog } from '../components/ShareDialog';
 
 const API_BASE = import.meta.env.VITE_API_BASE || '';
 
@@ -25,6 +27,7 @@ export function Dashboard({ onOpenProject }: DashboardProps) {
   const [showCreate, setShowCreate] = useState(false);
   const [newName, setNewName] = useState('');
   const [newDesc, setNewDesc] = useState('');
+  const [shareProjectId, setShareProjectId] = useState<string | null>(null);
 
   const fetchProjects = useCallback(async () => {
     setLoading(true);
@@ -86,7 +89,10 @@ export function Dashboard({ onOpenProject }: DashboardProps) {
           <h1>Web CAD</h1>
           <span className="dashboard-user">{user?.name} ({user?.role})</span>
         </div>
-        <button className="dashboard-logout" onClick={logout}>Abmelden</button>
+        <div className="dashboard-header-actions">
+          <NotificationPanel token={token!} />
+          <button className="dashboard-logout" onClick={logout}>Abmelden</button>
+        </div>
       </header>
 
       <div className="dashboard-content">
@@ -133,18 +139,33 @@ export function Dashboard({ onOpenProject }: DashboardProps) {
                 {project.description && <p>{project.description}</p>}
                 <div className="dashboard-project-meta">
                   <span>Erstellt: {new Date(project.created_at).toLocaleDateString('de-DE')}</span>
-                  <button
-                    className="dashboard-delete-btn"
-                    onClick={(e) => handleDelete(project.id, e)}
-                  >
-                    Löschen
-                  </button>
+                  <div className="dashboard-project-actions">
+                    <button
+                      className="dashboard-share-btn"
+                      onClick={(e) => { e.stopPropagation(); setShareProjectId(project.id); }}
+                    >
+                      Teilen
+                    </button>
+                    <button
+                      className="dashboard-delete-btn"
+                      onClick={(e) => handleDelete(project.id, e)}
+                    >
+                      Löschen
+                    </button>
+                  </div>
                 </div>
               </div>
             ))}
           </div>
         )}
       </div>
+
+      <ShareDialog
+        token={token!}
+        projectId={shareProjectId ?? ''}
+        open={!!shareProjectId}
+        onClose={() => setShareProjectId(null)}
+      />
     </div>
   );
 }

frontend/src/services/api.ts

@@ -387,6 +387,81 @@ export async function loadProjectDataTyped(token: string, projectId: string): Pr
   return promise;
 }
 
+// ─── Notifications ───────────────────────────────────────
+export interface NotificationItem {
+  id: string;
+  user_id: string;
+  type: string;
+  title: string;
+  message: string;
+  read: number;
+  created_at: string;
+}
+
+export async function getNotifications(token: string): Promise<NotificationItem[]> {
+  const res = await fetch(`${API_BASE}/api/notifications`, { headers: authHeaders(token) });
+  if (!res.ok) throw new Error('Failed to load notifications');
+  return res.json();
+}
+
+export async function createNotification(token: string, data: { type?: string; title: string; message: string; user_id?: string }): Promise<NotificationItem> {
+  const res = await fetch(`${API_BASE}/api/notifications`, {
+    method: 'POST',
+    headers: authHeaders(token),
+    body: JSON.stringify(data),
+  });
+  if (!res.ok) throw new Error('Failed to create notification');
+  return res.json();
+}
+
+export async function markNotificationRead(token: string, id: string): Promise<void> {
+  await fetch(`${API_BASE}/api/notifications/${id}/read`, {
+    method: 'PATCH',
+    headers: authHeaders(token),
+  });
+}
+
+export async function deleteNotification(token: string, id: string): Promise<void> {
+  await fetch(`${API_BASE}/api/notifications/${id}`, {
+    method: 'DELETE',
+    headers: authHeaders(token),
+  });
+}
+
+// ─── Project Shares ──────────────────────────────────────
+export interface ProjectShare {
+  id: string;
+  project_id: string;
+  shared_with_email: string;
+  shared_by: string;
+  permission: string;
+  share_token: string | null;
+  created_at: string;
+}
+
+export async function getProjectShares(token: string, projectId: string): Promise<ProjectShare[]> {
+  const res = await fetch(`${API_BASE}/api/projects/${projectId}/shares`, { headers: authHeaders(token) });
+  if (!res.ok) throw new Error('Failed to load shares');
+  return res.json();
+}
+
+export async function createProjectShare(token: string, projectId: string, data: { shared_with_email: string; permission?: string }): Promise<ProjectShare> {
+  const res = await fetch(`${API_BASE}/api/projects/${projectId}/shares`, {
+    method: 'POST',
+    headers: authHeaders(token),
+    body: JSON.stringify(data),
+  });
+  if (!res.ok) throw new Error('Failed to create share');
+  return res.json();
+}
+
+export async function deleteProjectShare(token: string, shareId: string): Promise<void> {
+  await fetch(`${API_BASE}/api/shares/${shareId}`, {
+    method: 'DELETE',
+    headers: authHeaders(token),
+  });
+}
+
 export { API_BASE };
 
 // ─── AI Copilot ─────────────────────────────────────────

frontend/src/styles.css

@@ -2010,3 +2010,109 @@ body.drawer-open { overflow: hidden; }
   padding: 3px 8px;
   border-radius: 4px;
 }
+/* ─── Notification Panel ─────────────────────────────── */
+.dashboard-header-actions { display: flex; align-items: center; gap: 12px; }
+.notification-panel-wrapper { position: relative; }
+.notification-bell-btn {
+  position: relative; background: none; border: none; cursor: pointer;
+  color: var(--color-text-muted); padding: 6px; border-radius: 6px; transition: background 0.2s;
+}
+.notification-bell-btn:hover { background: var(--color-border); }
+.notification-badge {
+  position: absolute; top: 0; right: 0; background: var(--color-primary); color: white;
+  font-size: 10px; font-weight: 700; min-width: 16px; height: 16px; border-radius: 8px;
+  display: flex; align-items: center; justify-content: center; padding: 0 4px;
+}
+.notification-dropdown {
+  position: absolute; top: 100%; right: 0; margin-top: 8px; width: 360px;
+  background: var(--color-bg); border: 1px solid var(--color-border); border-radius: 8px;
+  box-shadow: 0 8px 24px rgba(0,0,0,0.3); z-index: 1000; max-height: 480px; overflow-y: auto;
+}
+.notification-dropdown-header {
+  display: flex; justify-content: space-between; align-items: center;
+  padding: 12px 16px; border-bottom: 1px solid var(--color-border);
+}
+.notification-dropdown-header h3 { margin: 0; font-size: 14px; font-weight: 600; }
+.notification-close { background: none; border: none; cursor: pointer; font-size: 18px; color: var(--color-text-muted); }
+.notification-loading, .notification-empty { padding: 16px; text-align: center; color: var(--color-text-muted); font-size: 13px; }
+.notification-list { padding: 4px 0; }
+.notification-item {
+  display: flex; justify-content: space-between; align-items: flex-start;
+  padding: 10px 16px; border-bottom: 1px solid var(--color-border); gap: 8px;
+}
+.notification-item.unread { background: rgba(52, 152, 219, 0.08); }
+.notification-item-content { display: flex; flex-direction: column; gap: 2px; flex: 1; min-width: 0; }
+.notification-type-badge {
+  font-size: 10px; text-transform: uppercase; font-weight: 600; color: var(--color-text-muted);
+  padding: 1px 6px; border-radius: 3px; background: var(--color-border); align-self: flex-start;
+}
+.notification-type-badge.type-share { color: #2ecc71; background: rgba(46, 204, 113, 0.15); }
+.notification-type-badge.type-info { color: #3498db; background: rgba(52, 152, 219, 0.15); }
+.notification-title { font-size: 13px; font-weight: 600; color: var(--color-text); }
+.notification-message { font-size: 12px; color: var(--color-text-muted); line-height: 1.4; }
+.notification-time { font-size: 11px; color: var(--color-text-muted); margin-top: 2px; }
+.notification-item-actions { display: flex; gap: 4px; flex-shrink: 0; }
+.notification-action-btn {
+  background: none; border: none; cursor: pointer; padding: 4px;
+  color: var(--color-text-muted); border-radius: 4px; transition: background 0.2s;
+}
+.notification-action-btn:hover { background: var(--color-border); }
+.notification-action-btn.delete:hover { color: #e74c3c; }
+
+/* ─── Share Dialog ────────────────────────────────────── */
+.share-dialog-overlay {
+  position: fixed; top: 0; left: 0; right: 0; bottom: 0;
+  background: rgba(0,0,0,0.5); display: flex; align-items: center; justify-content: center; z-index: 2000;
+}
+.share-dialog {
+  background: var(--color-bg); border: 1px solid var(--color-border); border-radius: 12px;
+  width: 440px; max-width: 90vw; max-height: 80vh; overflow-y: auto; box-shadow: 0 16px 48px rgba(0,0,0,0.4);
+}
+.share-dialog-header {
+  display: flex; justify-content: space-between; align-items: center;
+  padding: 16px 20px; border-bottom: 1px solid var(--color-border);
+}
+.share-dialog-header h3 { margin: 0; font-size: 16px; font-weight: 600; }
+.share-dialog-close { background: none; border: none; cursor: pointer; font-size: 20px; color: var(--color-text-muted); }
+.share-dialog-body { padding: 20px; }
+.share-form { display: flex; gap: 8px; margin-bottom: 16px; }
+.share-email-input {
+  flex: 1; padding: 8px 12px; border: 1px solid var(--color-border); border-radius: 6px;
+  background: var(--color-bg); color: var(--color-text); font-size: 13px;
+}
+.share-permission-select {
+  padding: 8px 12px; border: 1px solid var(--color-border); border-radius: 6px;
+  background: var(--color-bg); color: var(--color-text); font-size: 13px;
+}
+.share-add-btn {
+  padding: 8px 16px; border: none; border-radius: 6px; cursor: pointer;
+  background: var(--color-primary); color: white; font-size: 13px; font-weight: 600;
+}
+.share-add-btn:hover { opacity: 0.9; }
+.share-error { color: #e74c3c; font-size: 12px; margin: 8px 0; }
+.share-loading, .share-empty { padding: 16px; text-align: center; color: var(--color-text-muted); font-size: 13px; }
+.share-list { display: flex; flex-direction: column; gap: 8px; }
+.share-item {
+  display: flex; justify-content: space-between; align-items: center;
+  padding: 10px 12px; border: 1px solid var(--color-border); border-radius: 6px;
+}
+.share-item-info { display: flex; align-items: center; gap: 8px; }
+.share-email { font-size: 13px; color: var(--color-text); }
+.share-permission-badge {
+  font-size: 10px; text-transform: uppercase; font-weight: 600; padding: 2px 8px;
+  border-radius: 4px; background: var(--color-border); color: var(--color-text-muted);
+}
+.share-remove-btn {
+  background: none; border: none; cursor: pointer; padding: 4px;
+  color: var(--color-text-muted); border-radius: 4px; transition: color 0.2s;
+}
+.share-remove-btn:hover { color: #e74c3c; }
+
+/* ─── Dashboard Share Button ──────────────────────────── */
+.dashboard-project-actions { display: flex; gap: 6px; }
+.dashboard-share-btn {
+  padding: 4px 10px; border: 1px solid var(--color-border); border-radius: 4px;
+  background: transparent; color: var(--color-text-muted); cursor: pointer; font-size: 12px;
+}
+.dashboard-share-btn:hover { border-color: var(--color-primary); color: var(--color-primary); }
+