fix(release): notarize and staple macOS DMGs (#523)

* fix(release): notarize and staple macOS DMGs

Tauri's bundler signs the .app and notarizes it, but ships the .dmg
wrapper unnotarized. Gatekeeper rejects that on macOS 15 Sequoia
(caught by Homebrew Cask CI) and causes the 'app isn't signed'
dialog on older Intel Macs when Apple's notarization servers are
slow (issue #509).

New step submits each built DMG to notarytool, staples the ticket,
verifies with spctl, then overwrites the release asset tauri-action
already uploaded to the draft release.

Adds ~5-10 min per macOS job (notarytool round-trip).

* fix(release): fail loudly when no DMG is found to notarize

Empty glob + nullglob was silently skipping the loop body, so if
Tauri's bundler output path changed we'd re-publish the unnotarized
DMGs with a green CI. Assert the glob matched at least one file.

* fix(release): resolve release tag from tauri.conf.json, not GITHUB_REF_NAME

GITHUB_REF_NAME is the branch name when the workflow runs via
workflow_dispatch, so the gh release upload targeted the wrong thing
on manual runs. tauri-action derives its tag from tauri.conf.json's
version field via the v__VERSION__ template; use the same source so
the two always agree.

.github/workflows/release.yml

@@ -226,6 +226,46 @@ jobs:
           args: ${{ matrix.args }}
           includeUpdaterJson: true
 
+      # Tauri's bundler signs the .app and notarizes it, but the .dmg wrapper
+      # ships unnotarized. Gatekeeper rejects that on macOS 15 Sequoia (caught
+      # by Homebrew Cask CI) and causes "app isn't signed" dialogs on older
+      # Intel Macs when Apple's notarization servers are slow (see issue #509).
+      # Submit the .dmg to notarytool, staple the ticket, and overwrite the
+      # release asset uploaded by tauri-action.
+      - name: Notarize and staple DMG (macOS)
+        if: matrix.platform == 'macos-latest' || matrix.platform == 'macos-15-intel'
+        env:
+          APPLE_API_KEY_ID: ${{ secrets.APPLE_API_KEY }}
+          APPLE_API_ISSUER: ${{ secrets.APPLE_API_ISSUER }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          set -euo pipefail
+          KEY_PATH="$HOME/.appstoreconnect/private_keys/AuthKey_${APPLE_API_KEY_ID}.p8"
+          TARGET=$(echo "${{ matrix.args }}" | sed -n 's/.*--target \([a-z0-9_-]*\).*/\1/p')
+          DMG_DIR="tauri/src-tauri/target/${TARGET}/release/bundle/dmg"
+          # Match the release tag tauri-action resolved from tauri.conf.json's
+          # version field; GITHUB_REF_NAME is a branch name under workflow_dispatch.
+          RELEASE_TAG="v$(jq -r '.version' tauri/src-tauri/tauri.conf.json)"
+          shopt -s nullglob
+          dmgs=("${DMG_DIR}"/*.dmg)
+          if [ ${#dmgs[@]} -eq 0 ]; then
+            echo "::error::No DMGs found in ${DMG_DIR} — tauri bundler output path may have changed"
+            exit 1
+          fi
+          for dmg in "${dmgs[@]}"; do
+            echo "::group::Notarize $(basename "$dmg")"
+            xcrun notarytool submit "$dmg" \
+              --key "$KEY_PATH" \
+              --key-id "$APPLE_API_KEY_ID" \
+              --issuer "$APPLE_API_ISSUER" \
+              --wait --timeout 20m
+            xcrun stapler staple "$dmg"
+            spctl -a -t open --context context:primary-signature -vv "$dmg"
+            gh release upload "${RELEASE_TAG}" "$dmg" --clobber \
+              --repo "${GITHUB_REPOSITORY}"
+            echo "::endgroup::"
+          done
+
   build-cuda-windows:
     runs-on: windows-latest
     permissions: