feat: dashboard UI improvements - 8 changes

1. Web CAD title larger (24px, font-weight 800)
2. Gear icon opens SettingsModal
3. Folder drag-and-drop with nested folders (backend parent_id support)
4. Icon-only card buttons with CSS tooltips
5. Canvas preview (deterministic SVG per project)
6. Info panel: smaller title, double-height description
7. User/group permission selector
8. oe → ö correction

backend/src/routes/projectFolders.ts

@@ -62,10 +62,15 @@ export function registerProjectFolderRoutes(fastify: FastifyInstance, db: Databa
     const folder = db.getProjectFolder(id);
     if (!folder) return reply.code(404).send({ error: 'Folder not found' });
     if (folder.owner_id !== user.id) return reply.code(403).send({ error: 'Forbidden' });
-    const body = request.body as { name?: string };
-    const nameErr = validateName(body.name, 'name');
-    if (nameErr) return reply.code(400).send({ error: nameErr });
-    const updated = db.updateProjectFolder(id, { name: body.name });
+    const body = request.body as { name?: string; parent_id?: string | null };
+    const updates: Partial<{ name: string; parent_id: string | null }> = {};
+    if (body.name !== undefined) {
+      const nameErr = validateName(body.name, 'name');
+      if (nameErr) return reply.code(400).send({ error: nameErr });
+      updates.name = body.name;
+    }
+    if (body.parent_id !== undefined) updates.parent_id = body.parent_id;
+    const updated = db.updateProjectFolder(id, updates);
     if (!updated) return reply.code(404).send({ error: 'Folder not found' });
     return updated;
   });