fix(tickets): fix permissions toast, board fallback, assignment search, remove load more

- list_resources: return [] on PSAError instead of 502 — stops global interceptor
  toast when CW API key lacks ticket members permission (Lesson 111)
- list_boards/list_priorities: add warning logging so Railway logs reveal the
  root cause when CW permissions are missing
- TicketsPage: derive board options from ticket search results when listBoards
  returns empty (CW permissions fallback)
- TicketFilterBar: replace assignment <select> with searchable member picker —
  fixed options (All/Mine/Unassigned) + text-filtered member dropdown
- TicketQueue: remove Load More / infinite scroll; page now exists at /tickets

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

backend/app/api/endpoints/integrations.py

@@ -376,8 +376,9 @@ async def list_boards(
         provider = await get_provider_for_account(current_user.account_id, db)
         boards = await provider.list_boards()
         return [PSABoardResponse(id=b.id, name=b.name) for b in boards]
-    except PSAError:
+    except PSAError as e:
         # Boards are optional UI chrome — degrade gracefully rather than surfacing a toast
+        logger.warning("list_boards failed: %s", e)
         return []
 
 
@@ -630,7 +631,9 @@ async def list_ticket_resources(
     try:
         return await ticket_svc.list_resources(current_user.account_id, ticket_id, db)
     except PSAError as e:
-        raise HTTPException(status_code=502, detail=str(e))
+        # Resources are optional display data — degrade gracefully rather than surfacing a toast
+        logger.warning("list_resources(%s) failed: %s", ticket_id, e)
+        return []
 
 
 @router.post("/tickets/{ticket_id}/resources", response_model=PSAResourceSchema, status_code=201)
@@ -679,7 +682,8 @@ async def list_priorities(
         provider = await get_provider_for_account(current_user.account_id, db)
         raw = await provider.list_priorities()
         return [PSAPrioritySchema(id=p["id"], name=p["name"]) for p in raw if p.get("id")]
-    except PSAError:
+    except PSAError as e:
+        logger.warning("list_priorities failed: %s", e)
         return []