fix: queue stuck on "Busy" for "Any Model" jobs (#435)

When a print was queued with "Any [Model]", the queue widget only
queried items with printer_id=X after dispatch, missing the next
pending model-based item (printer_id IS NULL, target_model="P1S").
The "Clear Plate & Start Next" button never appeared, leaving the
scheduler stuck reporting "Busy".

Add optional target_model query parameter to GET /queue/. When
combined with printer_id, uses OR logic to also return unassigned
items whose target_model matches. The frontend now passes the
printer's model through PrinterQueueWidget to this query.

frontend/src/api/client.ts

@@ -3188,10 +3188,11 @@ export const api = {
     request<HASensorEntity[]>('/smart-plugs/ha/sensors'),
 
   // Print Queue
-  getQueue: (printerId?: number, status?: string) => {
+  getQueue: (printerId?: number, status?: string, targetModel?: string) => {
     const params = new URLSearchParams();
     if (printerId) params.set('printer_id', String(printerId));
     if (status) params.set('status', status);
+    if (targetModel) params.set('target_model', targetModel);
     return request<PrintQueueItem[]>(`/queue/?${params}`);
   },
   getQueueItem: (id: number) => request<PrintQueueItem>(`/queue/${id}`),