refactor(collab): remove live document collaboration and enforce strictly read-only sharing

frontend/src/lib/api.ts

@@ -5,10 +5,6 @@ import {
   Document,
   DocumentBlock,
   DocShare,
-  DocLockInfo,
-  BlockLockInfo,
-  LiveSessionInfo,
-  DocLocksResponse,
   KanbanColumn,
   ListItem,
   ListShare,
@@ -641,46 +637,6 @@ export const api = {
     await request(`/api/v1/documents/${id}`, { method: 'DELETE' });
   },
 
-  async getDocLocks(docId: string): Promise<DocLocksResponse> {
-    const res = await request<DocLocksResponse>(`/api/v1/documents/${docId}/locks`);
-    return {
-      liveSession: res.liveSession || null,
-      blockLocks: ensureArray(res.blockLocks),
-    };
-  },
-
-  async lockBlock(docId: string, blockId: string, userColor?: string, ttlSeconds: number = 30): Promise<BlockLockInfo> {
-    console.log(`[MindSift Lock] Lock anfordern für Block "${blockId}" in Notiz "${docId}"...`);
-    const res = await request<any>(`/api/v1/documents/${docId}/blocks/${encodeURIComponent(blockId)}/lock`, {
-      method: 'POST',
-      body: JSON.stringify({ userColor, ttlSeconds, ttl: ttlSeconds }),
-    });
-    console.log(`[MindSift Lock] Lock erfolgreich erhalten für "${blockId}":`, res?.lock || res);
-    return res?.lock || res;
-  },
-
-  async unlockBlock(docId: string, blockId: string): Promise<{ status: string }> {
-    console.log(`[MindSift Lock] Lock freigeben für Block "${blockId}" in Notiz "${docId}"...`);
-    const res = await request<{ status: string }>(`/api/v1/documents/${docId}/blocks/${encodeURIComponent(blockId)}/unlock`, {
-      method: 'POST',
-    });
-    console.log(`[MindSift Lock] Lock freigegeben für "${blockId}"`);
-    return res;
-  },
-
-  async startLiveSession(docId: string): Promise<LiveSessionInfo> {
-    const res = await request<any>(`/api/v1/documents/${docId}/live/start`, {
-      method: 'POST',
-    });
-    return res?.session || res;
-  },
-
-  async endLiveSession(docId: string): Promise<{ status: string }> {
-    return request<{ status: string }>(`/api/v1/documents/${docId}/live/end`, {
-      method: 'POST',
-    });
-  },
-
   async moveDocument(id: string, folderPath: string): Promise<Document> {
     const d = await request<Document>(`/api/v1/documents/${id}/move`, {
       method: 'PUT',