Fix photos download (remove invalid --convert-all-heic-to-jpeg flag); block duplicate auth requests

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

icloud_gui.py

@@ -982,7 +982,7 @@ class PhotosPage(Gtk.Box):
             "--password",         password,
             "--cookie-directory", cookie_dir,
             "--directory",        PHOTOS_MOUNT,
-            "--convert-all-heic-to-jpeg",
+            "--skip-live-photos",
             "--no-progress-bar",
         ]
         if recent:
@@ -1187,6 +1187,9 @@ class AuthPage(Gtk.Box):
         self.pack_start(tfa_card, False, False, 0)
 
     def _on_auth(self, btn):
+        # Kill any previous auth process so only one request goes to Apple
+        if hasattr(self, "_auth_proc") and self._auth_proc and self._auth_proc.poll() is None:
+            return  # already in flight, do nothing
         btn.set_sensitive(False)
         btn.set_label("Waiting for Apple…")
         self._auth_btn = btn