Fix macOS/iOS CI: chmod needs sudo, Nix store frameworks are root-owned

.github/workflows/ios.yml

@@ -22,7 +22,18 @@ jobs:
           extra_nix_config: experimental-features = nix-command flakes flake-self-attrs
 
       - name: Build app
-        run: nix develop --command bash -c "flutter pub get && dart scripts/generate.dart && flutter pub run build_runner build && flutter build ios --release --no-codesign"
+        run: |
+          nix develop --command bash -c '
+            set -e
+            flutter pub get
+            dart scripts/generate.dart
+            flutter pub run build_runner build
+
+            FLUTTER_ROOT="$(dirname "$(dirname "$(readlink -f "$(command -v flutter)")")")"
+            sudo find -L "$FLUTTER_ROOT" -type d -iname "*.framework" -exec chmod -R u+w {} +
+
+            flutter build ios --release --no-codesign
+          '
 
       # Unsigned IPA: SideStore/AltStore re-sign this on-device with the
       # user's own Apple ID at install time, so no certificate is needed here.