no-mistakes(review): Guard photo cleanup; add transitions helper and assign auto-advance

app/routers/tickets.py

@@ -2,6 +2,7 @@
 
 from __future__ import annotations
 
+import logging
 import uuid
 from datetime import datetime
 from pathlib import Path
@@ -32,6 +33,8 @@ from app.schemas.ticket import (
 from app.services import ticket as ticket_service
 from app.services.sla import get_sla_status
 
+logger = logging.getLogger(__name__)
+
 router = APIRouter(prefix="/api/tickets", tags=["tickets"])
 
 # Ensure uploads directory exists
@@ -224,6 +227,19 @@ async def list_tickets(
     return TicketListResponse(items=items, total=total, page=page, page_size=page_size)
 
 
+@router.get("/{ticket_id}/transitions")
+async def get_ticket_transitions(
+    ticket_id: int,
+    db: Annotated[AsyncSession, Depends(get_db)],
+) -> dict:
+    """Return the valid next statuses for a ticket's current status."""
+    ticket = await ticket_service.get_ticket(db, ticket_id)
+    return {
+        "current_status": ticket.status,
+        "transitions": ticket_service.VALID_TRANSITIONS.get(ticket.status, []),
+    }
+
+
 @router.get("/{ticket_id}", response_model=TicketOut)
 async def get_ticket(
     ticket_id: int,
@@ -266,7 +282,14 @@ async def delete_ticket(
     for photo in ticket.photos:
         if photo.photo_url:
             name = photo.photo_url.rsplit("/", 1)[-1]
-            (UPLOADS_DIR / name).unlink(missing_ok=True)
+            try:
+                (UPLOADS_DIR / name).unlink(missing_ok=True)
+            except OSError:
+                logger.warning(
+                    "Could not remove orphaned photo file %s for ticket %s",
+                    name,
+                    ticket_id,
+                )
 
 
 # ── Status Transitions (convenience endpoints) ───────────────────────