feat: implement comments and activity panel in workspace

- Added CommentsPanel component for managing comments on documents.
- Integrated comment creation, deletion, and resolution functionalities.
- Implemented activity tracking for document interactions.
- Enhanced SketchPage with editing and saving capabilities.
- Introduced template management API endpoints for creating, sharing, and deleting templates.
- Added runtime validation report for frontend and backend.
- Created GettingStartedPanel for user onboarding with template options.
- Implemented Playwright E2E tests for accessibility and export functionality.

backend/app/services/history_service.py

@@ -0,0 +1,81 @@
+import uuid
+from datetime import UTC, datetime
+from typing import Any
+
+from motor.motor_asyncio import AsyncIOMotorDatabase
+from pymongo import ReturnDocument
+
+from app.services.document_service import access_query, can_edit
+
+COLLECTION = "document_versions"
+
+
+async def ensure_history_indexes(db: AsyncIOMotorDatabase) -> None:
+    await db[COLLECTION].create_index([("document_id", 1), ("created_at", -1)])
+
+
+def serialize_version(version: dict[str, Any]) -> dict[str, Any]:
+    return {
+        "id": version["_id"],
+        "document_id": version["document_id"],
+        "title": version["title"],
+        "content": version.get("content", {}),
+        "created_by": version["created_by"],
+        "created_at": version["created_at"],
+        "reason": version.get("reason", "Updated"),
+    }
+
+
+async def create_version(
+    db: AsyncIOMotorDatabase,
+    document: dict[str, Any],
+    actor_id: int,
+    actor_name: str,
+    reason: str,
+) -> None:
+    if not can_edit(document, actor_id):
+        return
+    await db[COLLECTION].insert_one({
+        "_id": str(uuid.uuid4()),
+        "document_id": document["_id"],
+        "title": document["title"],
+        "content": document.get("content", {}),
+        "created_by": actor_name,
+        "created_at": datetime.now(UTC),
+        "reason": reason,
+    })
+
+
+async def list_versions(
+    db: AsyncIOMotorDatabase,
+    document_id: str,
+    user_id: int,
+) -> list[dict[str, Any]] | None:
+    document = await db["documents"].find_one({"_id": document_id, **access_query(user_id)})
+    if document is None:
+        return None
+    cursor = db[COLLECTION].find({"document_id": document_id}).sort("created_at", -1).limit(50)
+    return [serialize_version(version) async for version in cursor]
+
+
+async def restore_version(
+    db: AsyncIOMotorDatabase,
+    document_id: str,
+    version_id: str,
+    user_id: int,
+    actor_name: str,
+) -> dict[str, Any] | None:
+    document = await db["documents"].find_one({"_id": document_id, **access_query(user_id)})
+    if document is None or not can_edit(document, user_id):
+        return None
+    version = await db[COLLECTION].find_one({"_id": version_id, "document_id": document_id})
+    if version is None:
+        return None
+    await create_version(db, document, user_id, actor_name, "Before restore")
+    now = datetime.now(UTC)
+    updated = await db["documents"].find_one_and_update(
+        {"_id": document_id},
+        {"$set": {"title": version["title"], "content": version.get("content", {}), "updated_at": now}},
+        return_document=ReturnDocument.AFTER,
+    )
+    return updated