Build app bundles on release branches always (#3789)

.github/workflows/bundle-desktop.yml

@@ -39,6 +39,8 @@ jobs:
     permissions:
       id-token: write
       contents: read
+    outputs:
+        artifact-url: ${{ steps.upload-app-bundle.outputs.artifact-url }}
     steps:
       # Debug information about the workflow and inputs
       - name: Debug workflow info
@@ -294,6 +296,7 @@ jobs:
           df -h
 
       - name: Upload Desktop artifact
+        id: upload-app-bundle
         uses: actions/upload-artifact@4cec3d8aa04e39d1a68397de0c4cd6fb9dce8ec1 # pin@v4
         with:
           name: Goose-darwin-arm64

.github/workflows/release-branches.yml

@@ -0,0 +1,34 @@
+name: Build Goose Release Candidate
+
+on:
+  pull_request:
+
+jobs:
+  bundle-desktop:
+    if: startsWith(github.head_ref, 'release/')
+    uses: ./.github/workflows/bundle-desktop.yml
+    permissions:
+      id-token: write
+      contents: read
+    with:
+      signing: true
+
+  comment-on-pr:
+    needs: bundle-desktop
+    runs-on: ubuntu-latest
+    permissions:
+      pull-requests: write
+    steps:
+      - name: Comment with download link
+        uses: peter-evans/create-or-update-comment@71345be0265236311c031f5c7866368bd1eff043 # pin@v4
+        with:
+          issue-number: ${{ github.event.number }}
+          body: |
+            ### macOS ARM64 Desktop App (Apple Silicon)
+
+            [📱 Download macOS Desktop App (arm64, signed)](https://nightly.link/${{ github.repository }}/actions/runs/${{ github.run_id }}/Goose-darwin-arm64.zip)
+
+            **Instructions:**
+            After downloading, unzip the file and drag the Goose.app to your Applications folder. The app is signed and notarized for macOS.
+
+            This link is provided by nightly.link and will work even if you're not logged into GitHub.