fix: workaround for immutable releases breaking chart-releaser

GitHub's immutable releases feature (GA since Oct 2025) breaks the
standard chart-releaser because it creates releases first, then uploads
assets separately. With immutable releases, once the release is created,
assets cannot be added.

This workaround builds a patched chart-releaser from
helm/chart-releaser#587 that creates releases
as drafts first, uploads assets, then publishes the release.

Relates to: helm/chart-releaser-action#228

Author: chrisburr

.github/workflows/release.yml

@@ -23,9 +23,25 @@ jobs:
           git config user.name "$GITHUB_ACTOR"
           git config user.email "$GITHUB_ACTOR@users.noreply.github.com"
 
+      # Workaround for https://github.com/helm/chart-releaser-action/issues/228
+      # GitHub's immutable releases feature breaks the standard chart-releaser.
+      # This builds a patched version that creates releases as drafts first.
+      # TODO: Remove once https://github.com/helm/chart-releaser/pull/587 is released
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.21'
+
+      - name: Build patched chart-releaser
+        run: |
+          git clone --depth 1 -b fix/immutable-releases https://github.com/chrisburr/chart-releaser.git /tmp/chart-releaser
+          cd /tmp/chart-releaser
+          go build -o ${{ runner.tool_cache }}/cr/patched/cr ./cr
+
       - name: Run chart-releaser
         uses: helm/chart-releaser-action@v1.7.0
         with:
           charts_dir: .
+          install_dir: ${{ runner.tool_cache }}/cr/patched
         env:
           CR_TOKEN: "${{ secrets.GITHUB_TOKEN }}"