Fix: Abbrechen-Dialog, Overlay-Stacking, Queue-Cancel

1. Confirm-Dialog z-index ueber Progress-Popup (10000 > 9000)
2. Progress-Popup wird ausgeblendet waehrend Confirm-Dialog offen
3. Kein dunkler-werdendes Overlay bei mehrfachem Abbrechen-Klick
4. Abbrechen funktioniert jetzt auch fuer Lagen in der Warteschlange
   (werden direkt aus der Queue entfernt statt auf Start zu warten)
5. Cancel-Status wird im Popup-Titel angezeigt

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/agents/orchestrator.py

@@ -437,22 +437,59 @@ class AgentOrchestrator:
         return True
 
     async def cancel_refresh(self, incident_id: int) -> bool:
-        """Fordert Abbruch eines laufenden Refreshes an."""
-        if self._current_task != incident_id:
-            return False
-        self._cancel_requested.add(incident_id)
-        logger.info(f"Cancel angefordert fuer Lage {incident_id}")
-        if self._ws_manager:
-            try:
-                vis, cb, tid = await self._get_incident_visibility(incident_id)
-            except Exception:
-                vis, cb, tid = "public", None, None
-            await self._ws_manager.broadcast_for_incident({
-                "type": "status_update",
-                "incident_id": incident_id,
-                "data": {"status": "cancelling", "detail": "Wird abgebrochen..."},
-            }, vis, cb, tid)
-        return True
+        """Fordert Abbruch eines laufenden oder wartenden Refreshes an."""
+        # Check if it's the currently running task
+        if self._current_task == incident_id:
+            self._cancel_requested.add(incident_id)
+            logger.info(f"Cancel angefordert fuer laufende Lage {incident_id}")
+            if self._ws_manager:
+                try:
+                    vis, cb, tid = await self._get_incident_visibility(incident_id)
+                except Exception:
+                    vis, cb, tid = "public", None, None
+                await self._ws_manager.broadcast_for_incident({
+                    "type": "status_update",
+                    "incident_id": incident_id,
+                    "data": {"status": "cancelling", "detail": "Wird abgebrochen..."},
+                }, vis, cb, tid)
+            return True
+
+        # Check if it's in the queue (not yet started)
+        if incident_id in self._queued_ids:
+            self._queued_ids.discard(incident_id)
+            # Remove from asyncio queue (rebuild without this ID)
+            removed = False
+            new_items = []
+            while not self._queue.empty():
+                try:
+                    item = self._queue.get_nowait()
+                    iid = item[0] if isinstance(item, tuple) else item
+                    if iid == incident_id:
+                        removed = True
+                        self._queue.task_done()
+                    else:
+                        new_items.append(item)
+                except Exception:
+                    break
+            for item in new_items:
+                self._queue.put_nowait(item)
+
+            logger.info(f"Lage {incident_id} aus Warteschlange entfernt (removed={removed})")
+
+            # Send cancelled event
+            if self._ws_manager:
+                try:
+                    vis, cb, tid = await self._get_incident_visibility(incident_id)
+                except Exception:
+                    vis, cb, tid = "public", None, None
+                await self._ws_manager.broadcast_for_incident({
+                    "type": "refresh_cancelled",
+                    "incident_id": incident_id,
+                    "data": {"status": "cancelled"},
+                }, vis, cb, tid)
+            return True
+
+        return False
 
     def _check_cancelled(self, incident_id: int):
         """Prüft ob Abbruch angefordert wurde und wirft CancelledError."""