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

app/services/ticket.py

@@ -236,6 +236,7 @@ async def update_ticket(
     # Handle status transitions separately
     new_status = data.get("status")
     old_status = ticket.status
+    status_changed = new_status is not None and old_status != new_status
     if new_status is not None:
         if old_status != new_status:
             valid_targets = VALID_TRANSITIONS.get(old_status, [])
@@ -296,9 +297,25 @@ async def update_ticket(
 
             ticket.status = new_status
 
+    # Assigning a technician advances pre-Assigned tickets to Assigned with a
+    # timeline entry; tickets already past Assigned keep their current status.
+    advanced_to_assigned = False
+    if "assigned_to" in data and data["assigned_to"] != ticket.assigned_to:
+        if ticket.status in {"New", "Logged", "Triage"}:
+            await _log_status_change(
+                db,
+                ticket.id,
+                from_status=ticket.status,
+                to_status="Assigned",
+                note=data.get("note") if not status_changed else None,
+                user_id=user.id if user else None,
+            )
+            ticket.status = "Assigned"
+            advanced_to_assigned = True
+
     # Handle standalone note (no status change)
     note_only = data.get("note")
-    if note_only and not (new_status is not None and old_status != new_status):
+    if note_only and not status_changed and not advanced_to_assigned:
         await _log_status_change(
             db,
             ticket.id,