Fix cross-thread : QTimer.singleShot au lieu de pyqtSignal

pyqtSignal.emit() depuis un thread Python standard ne fonctionne pas.
Utilise QTimer.singleShot(0, callback) qui est thread-safe et
exécute le callback dans le thread principal Qt.

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

src/main.py

@@ -23,10 +23,7 @@ def main():
     port = config.get("server_port", 8080)
     host = config.get("server_ip", "0.0.0.0")
     upload_server = UploadServer(host=host, port=port)
-    upload_server.signals.photos_received.connect(
-        window.home_screen.notify_qr_photos,
-        Qt.ConnectionType.QueuedConnection
-    )
+    upload_server.set_callback(window.home_screen.notify_qr_photos)
     upload_server.start()
 
     # IMAP polling (Email)

src/services/upload_server.py

@@ -279,6 +279,7 @@ class UploadServer:
         self.host = host
         self.port = port
         self.signals = UploadSignals()
+        self._callback = None
         self.app = Flask(__name__)
         self._setup_routes()
         self._thread = None
@@ -308,10 +309,18 @@ class UploadServer:
                 saved.append(path)
 
             if saved:
-                self.signals.photos_received.emit(saved)
+                # QTimer.singleShot est thread-safe et exécute dans le thread principal
+                from PyQt6.QtCore import QTimer
+                from functools import partial
+                if self._callback:
+                    QTimer.singleShot(0, partial(self._callback, saved))
 
             return jsonify({"ok": True, "count": len(saved)})
 
+    def set_callback(self, callback):
+        """Définit le callback appelé quand des photos sont uploadées."""
+        self._callback = callback
+
     def start(self):
         """Démarre le serveur dans un thread daemon."""
         self._thread = threading.Thread(