Add clear selection button to status multi-select dropdown

Shows a separator and centered "Clear selection" at the bottom of the dropdown
when any statuses are selected. Clearing shows all tickets regardless of status.

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

client/src/pages/tickets/TicketFilters.tsx

@@ -164,6 +164,25 @@ export default function TicketFilters({
                 {STATUS_LABELS[s] ?? s}
               </DropdownMenuItem>
             ))}
+            {selectedStatuses.length > 0 && (
+              <>
+                <DropdownMenuSeparator />
+                <DropdownMenuItem
+                  onSelect={(e) => {
+                    e.preventDefault();
+                    onSetParams((prev) => {
+                      const next = new URLSearchParams(prev);
+                      next.set('status', '');
+                      next.delete('page');
+                      return next;
+                    });
+                  }}
+                  className="justify-center text-xs text-muted-foreground"
+                >
+                  Clear selection
+                </DropdownMenuItem>
+              </>
+            )}
           </DropdownMenuContent>
         </DropdownMenu>
 

client/src/pages/tickets/Tickets.tsx

@@ -44,7 +44,8 @@ export default function Tickets() {
   const { data: users = [] } = useUsers();
 
   const DEFAULT_STATUSES = 'OPEN,IN_PROGRESS';
-  const status = params.get('status') ?? DEFAULT_STATUSES;
+  const statusParam = params.get('status');
+  const status = statusParam === null ? DEFAULT_STATUSES : statusParam;
   const severity = params.get('severity') ?? '';
   const assigneeId = params.get('assigneeId') ?? '';
   const categoryId = params.get('categoryId') ?? '';