fix: auto-fix findings from no-mistakes review

- Remove duplicate  import
- Fix  →  in create ticket
- Fix  →  in ticket detail
- Add note field to TicketUpdate schema and handle note-only updates in backend
- Update frontend submitNote() to use PATCH endpoint

app/templates/tickets/detail.html

@@ -311,7 +311,7 @@
 
             async init() {
                 await this.loadTicket();
-                if (this.isFM || this.isAdmin) {
+                if (app().isFM || app().isAdmin) {
                     await this.loadTechnicians();
                 }
             },
@@ -392,9 +392,8 @@
                 if (!this.noteForm.note.trim()) return;
                 this.noteSubmitting = true;
                 try {
-                    // Use status update endpoint to add a note without changing status
-                    const updated = await app().apiPost(`/api/tickets/${this.ticketId}/status`, {
-                        status: this.ticket.status,
+                    // Use PATCH endpoint which now supports note-only updates
+                    const updated = await app().apiPatch(`/api/tickets/${this.ticketId}`, {
                         note: this.noteForm.note
                     });
                     this.ticket = updated;