Redesign doc service UX for scale + add group-based document sharing

- Three-column layout: Sidebar + SourcePanel (views + searchable category tree) + main
- DocumentSlideOver (480px right panel): inline editing, type picker, AI suggestion confirm/reject,
  categories combobox, tags editor, sharing section, raw text, re-analyse/delete actions
- ManageCategoriesDialog: inline rename, delete with confirm, search filter
- DocumentsPage rewrite: filter chip system, multi-file upload queue, drag-and-drop overlay,
  bulk actions bar (share/delete), smart TanStack Query polling, URL-driven view state
- Sidebar simplified: per-category NavLinks removed; Documents = single NavLink under Apps
- Backend: document_shares table (migration 0004), share CRUD endpoints, shared-with-me view,
  N+1-safe share_count via GROUP BY, recipient download access, X-User-Groups header enforcement
- Gateway proxy: injects X-User-Groups header into all document + category proxy requests
- Backend users: GET /api/users/me/groups endpoint for share picker combobox
- CLAUDE.md, STATUS.md files, and changelog updated

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

features/doc-service/app/schemas/document.py

@@ -27,6 +27,7 @@ class DocumentOut(BaseModel):
     watch_path: str | None = None
     suggested_folder: str | None = None
     suggested_filename: str | None = None
+    share_count: int = 0
 
     model_config = {"from_attributes": True}
 

features/doc-service/app/schemas/share.py

@@ -0,0 +1,41 @@
+from datetime import datetime
+
+from pydantic import BaseModel
+
+
+class DocumentShareOut(BaseModel):
+    id: str
+    document_id: str
+    group_id: str
+    shared_by_user_id: str
+    created_at: datetime
+
+    model_config = {"from_attributes": True}
+
+
+class DocumentShareCreate(BaseModel):
+    group_id: str
+
+
+class SharedDocumentOut(BaseModel):
+    """DocumentOut fields plus sharing context for the 'Shared with me' view."""
+    id: str
+    user_id: str
+    filename: str
+    title: str | None
+    file_size: int
+    status: str
+    document_type: str | None
+    extracted_data: str | None
+    tags: str | None
+    error_message: str | None
+    created_at: datetime
+    processed_at: datetime | None
+    categories: list = []
+    source: str = "upload"
+    share_count: int = 0
+    # Sharing context
+    shared_by_user_id: str
+    shared_via_group_id: str
+
+    model_config = {"from_attributes": True}