ci: auto-create app release on approved PR merge to main

.gitea/workflows/release.yml

@@ -0,0 +1,57 @@
+name: release
+
+on:
+  push:
+    branches:
+      - main
+
+permissions:
+  contents: write
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    if: github.event_name == 'push' && startsWith(github.event.head_commit.message, 'Merge pull request')
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Compute next version
+        id: version
+        run: |
+          latest=$(git tag --list 'v[0-9]*' --sort=-v:refname | head -n 1)
+          if [ -z "$latest" ]; then
+            next="v1.0.0"
+          else
+            latest=${latest#v}
+            IFS='.' read -r major minor patch <<< "$latest"
+            next="v${major}.${minor}.$((patch + 1))"
+          fi
+          echo "next=${next}" >> "$GITHUB_OUTPUT"
+
+      - name: Build changelog
+        id: changelog
+        run: |
+          prev_tag=$(git describe --tags --abbrev=0 2>/dev/null || echo "")
+          if [ -z "$prev_tag" ]; then
+            log=$(git log --oneline --no-merges main | head -n 40)
+          else
+            log=$(git log --oneline --no-merges "$prev_tag"..main | head -n 40)
+          fi
+          {
+            echo "body<<EOF"
+            echo "## What's new in this release"
+            echo ""
+            echo "$log" | sed 's/^/- /'
+            echo "EOF"
+          } >> "$GITHUB_OUTPUT"
+
+      - name: Create release
+        uses: softprops/action-gh-release@v2
+        with:
+          tag_name: ${{ steps.version.outputs.next }}
+          name: ${{ steps.version.outputs.next }}
+          body: ${{ steps.changelog.outputs.body }}
+          generate_release_notes: false