feat: Unified Messaging System — kommunikation plugin, AI/Proactive/System participants, MessageSidebar, Rich Content Renderer

Phase 1: Backend plugin kommunikation (13 files, 10 tables, REST API, WebSocket, RBAC, DMS Bridge, Participant Registry, Mini-App Registry, Search Provider)
Phase 2: AI plugins as participants (ai_assistant + ai_proactive dock as participants, heartbeat job)
Phase 3: system_notif plugin (system events → chat messages, pinned System room)
Phase 4: Frontend MessageSidebar (replaces AISidebar, same design, comm API client, WebSocket hook, commStore)
Phase 5: Rich Content Block Renderer (11 components: Markdown, HTML, Image, Audio, Video, File, ActionCard, ContactCard, MiniApp, BlockRenderer)
BasePlugin: added services property + _container in on_activate

frontend/src/store/commStore.ts

@@ -0,0 +1,107 @@
+import { create } from 'zustand';
+
+export interface Participant {
+  id: string;
+  conversation_id: string;
+  participant_id: string | null;
+  participant_type: string;
+  display_name: string | null;
+  role: string;
+}
+
+export interface Conversation {
+  id: string;
+  title: string | null;
+  is_locked: boolean;
+  locked_by: string | null;
+  is_direct: boolean;
+  is_archived: boolean;
+  is_pinned: boolean;
+  created_by: string | null;
+  created_by_type: string;
+  last_msg_at: string | null;
+  last_msg_preview: string | null;
+  last_msg_sender_type: string | null;
+  participants: Participant[];
+  unread_count: number;
+  metadata: Record<string, any>;
+}
+
+export interface MessageBlock {
+  id: string;
+  block_type: string;
+  block_data: Record<string, any>;
+  sort_order: number;
+}
+
+export interface MessageAttachment {
+  id: string;
+  file_id: string | null;
+  file_source: string;
+  file_name: string;
+  file_type: string;
+  file_size: number | null;
+  thumbnail_path: string | null;
+}
+
+export interface Message {
+  id: string;
+  conversation_id: string;
+  sender_id: string | null;
+  sender_type: string;
+  content: string;
+  content_format: string;
+  metadata: Record<string, any>;
+  reply_to_id: string | null;
+  is_pinned: boolean;
+  created_at: string | null;
+  edited_at: string | null;
+  blocks: MessageBlock[];
+  attachments: MessageAttachment[];
+  reactions: any[];
+}
+
+export interface CommState {
+  conversations: Conversation[];
+  activeConversationId: string | null;
+  messages: Record<string, Message[]>;
+  typingUsers: Record<string, string[]>;
+  unreadCounts: Record<string, number>;
+  loading: boolean;
+
+  setConversations: (convs: Conversation[]) => void;
+  setActiveConversation: (id: string | null) => void;
+  addMessage: (convId: string, msg: Message) => void;
+  setMessages: (convId: string, msgs: Message[]) => void;
+  updateConversation: (conv: Conversation) => void;
+  setTyping: (convId: string, userIds: string[]) => void;
+  setUnread: (convId: string, count: number) => void;
+  setLoading: (loading: boolean) => void;
+}
+
+export const useCommStore = create<CommState>((set) => ({
+  conversations: [],
+  activeConversationId: null,
+  messages: {},
+  typingUsers: {},
+  unreadCounts: {},
+  loading: false,
+  setConversations: (conversations) => set({ conversations }),
+  setActiveConversation: (activeConversationId) => set({ activeConversationId }),
+  addMessage: (convId, msg) => set((s) => ({
+    messages: { ...s.messages, [convId]: [...(s.messages[convId] || []), msg] },
+  })),
+  setMessages: (convId, msgs) => set((s) => ({
+    messages: { ...s.messages, [convId]: msgs },
+  })),
+  updateConversation: (conv) => set((s) => ({
+    conversations: s.conversations.map((c) => (c.id === conv.id ? conv : c)),
+  })),
+  setTyping: (convId, userIds) => set((s) => ({
+    typingUsers: { ...s.typingUsers, [convId]: userIds },
+  })),
+  setUnread: (convId, count) => set((s) => ({
+    unreadCounts: { ...s.unreadCounts, [convId]: count },
+  })),
+  setLoading: (loading) => set({ loading }),
+}));

frontend/src/store/uiStore.ts

@@ -18,6 +18,7 @@ export interface UIState {
   suggestionSidebarOpen: boolean;
   aiSidebarCollapsed: boolean;
   aiSidebarTab: AISidebarTab;
+  messageSidebarCollapsed: boolean;
   toasts: Toast[];
   notifications: string[];
   setTheme: (theme: Theme) => void;
@@ -29,6 +30,8 @@ export interface UIState {
   setAISidebarCollapsed: (collapsed: boolean) => void;
   setAISidebarTab: (tab: AISidebarTab) => void;
   openAISidebarProactive: () => void;
+  toggleMessageSidebar: () => void;
+  setMessageSidebarCollapsed: (collapsed: boolean) => void;
   addToast: (toast: Omit<Toast, 'id'>) => void;
   removeToast: (id: string) => void;
   clearToasts: () => void;
@@ -45,12 +48,9 @@ export const useUIStore = create<UIState>((set) => ({
   suggestionSidebarOpen: false,
   aiSidebarCollapsed: true,
   aiSidebarTab: 'chat',
+  messageSidebarCollapsed: true,
   toasts: [],
-  notifications: [
-    'Neuer Kontakt hinzugefügt: Max Mustermann',
-    'Firma aktualisiert: TechCorp GmbH',
-    'Meeting um 14:00 Uhr mit Müller AG',
-  ],
+  notifications: [],
   setTheme: (theme) => {
     localStorage.setItem('leocrm_theme', theme);
     set({ theme });
@@ -66,6 +66,8 @@ export const useUIStore = create<UIState>((set) => ({
   setAISidebarCollapsed: (collapsed) => set({ aiSidebarCollapsed: collapsed }),
   setAISidebarTab: (tab) => set({ aiSidebarTab: tab }),
   openAISidebarProactive: () => set({ aiSidebarCollapsed: false, aiSidebarTab: 'proactive' }),
+  toggleMessageSidebar: () => set((s) => ({ messageSidebarCollapsed: !s.messageSidebarCollapsed })),
+  setMessageSidebarCollapsed: (collapsed) => set({ messageSidebarCollapsed: collapsed }),
   addToast: (toast) => {
     const id = `toast-${++toastIdCounter}`;
     set((s) => ({ toasts: [...s.toasts, { ...toast, id }] }));