fix(db,chat): translate sslmode→ssl for asyncpg and rebind chat handler request param

* get_async_db_url now rewrites `sslmode=` to `ssl=` in the async DSN.
  asyncpg rejects the libpq-style `sslmode` query parameter, which made
  DatabaseSessionService.get_session_by_id explode with
  "connect() got an unexpected keyword argument 'sslmode'" whenever the
  managed Postgres URL required SSL.

* POST /api/v1/chat/{agent_id}/{session_id} was naming its Pydantic body
  `request`, shadowing the FastAPI Request used by error_response(). When
  the asyncpg crash above fired the generic except, error_response tried
  to read `request.url.path` on a ChatRequest model and raised
  AttributeError, hiding the real cause.
  Renamed the body to `payload` and added an explicit `request: Request`
  parameter for error responses.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: DavidsonGomes

src/api/chat_routes.py

@@ -31,6 +31,7 @@
     APIRouter,
     Depends,
     HTTPException,
+    Request,
     status,
     WebSocket,
     WebSocketDisconnect,
@@ -624,9 +625,10 @@ async def websocket_live_chat(
     }
 )
 async def chat(
-    request: ChatRequest,
+    payload: ChatRequest,
     agent_id: str,
     session_id: str,
+    request: Request,
     current_user: dict = Depends(get_current_user),
     db: Session = Depends(get_db),
     _: None = Depends(RequirePermission("ai_agent_processor", "execute")),
@@ -637,13 +639,13 @@ async def chat(
         final_response = await run_agent_adk(
             agent_id,
             user_id,
-            request.message,
+            payload.message,
             session_service,
             artifacts_service,
             memory_service,
             db,
             session_id=session_id,
-            files=request.files,
+            files=payload.files,
         )
 
         return success_response(

src/services/service_providers.py

@@ -40,21 +40,29 @@
 
 def get_async_db_url(db_url: str) -> str:
     """Convert PostgreSQL connection string to async format (postgresql+asyncpg://).
-    
+
+    asyncpg does not accept the libpq-style ``sslmode`` query parameter — it
+    uses ``ssl`` instead. We rewrite the URL so a single DSN with
+    ``sslmode=require`` (used by psycopg2 and the rest of the stack) still
+    works when the async driver picks it up.
+
     Args:
         db_url: PostgreSQL connection string (postgresql://...)
-        
+
     Returns:
-        Async PostgreSQL connection string (postgresql+asyncpg://...)
+        Async PostgreSQL connection string (postgresql+asyncpg://...) with
+        any ``sslmode=`` rewritten to ``ssl=``.
     """
     if db_url.startswith("postgresql://"):
-        return db_url.replace("postgresql://", "postgresql+asyncpg://", 1)
+        result = db_url.replace("postgresql://", "postgresql+asyncpg://", 1)
     elif db_url.startswith("postgresql+asyncpg://"):
-        return db_url
+        result = db_url
     else:
-        # If already in async format or other format, return as is
         return db_url
 
+    # asyncpg rejects `sslmode=`; translate it to `ssl=` keeping the value.
+    return result.replace("?sslmode=", "?ssl=").replace("&sslmode=", "&ssl=")
+
 
 # Initialize session service based on AI engine
 # DatabaseSessionService requires async driver (asyncpg)