ci: automate GitHub release notes generation

This updates the Maven Central release workflow to automatically generate and format GitHub release notes, replacing the manual process while preserving the exact same template.

Key changes:
* **Job Separation:** Splits the Maven deployment and release note generation into two distinct jobs. The `update-release-notes` job uses `needs: release` to ensure it only runs if the deployment succeeds.
* **Dynamic Tag Resolution:** Automatically calculates the previous version tag using semantic version sorting to generate the `Changelog` diff link.
* **Automated Issue Fetching:** Uses the GitHub CLI to dynamically fetch all closed issues and PRs associated with the release milestone, automatically formatting them into a markdown list and excluding items with the `dependencies` label.
* **Template Parity:** Recreates the custom manual layout, including the `Changes` section (with resolved milestone and dependency links) and the `Support my work` sponsor list.

Author: jknack

.github/workflows/maven-central.yml

@@ -29,7 +29,7 @@ jobs:
         run: mvn clean install -DskipTests -q
       - name: Set up Maven Central
         uses: actions/setup-java@v4
-        with: # running setup-java again overwrites the settings.xml
+        with:
           java-version: 21
           distribution: 'temurin'
           server-id: central
@@ -44,3 +44,60 @@ jobs:
           CENTRAL_USERNAME: ${{ secrets.CENTRAL_USERNAME }}
           CENTRAL_TOKEN: ${{ secrets.CENTRAL_TOKEN }}
           MAVEN_GPG_PASSPHRASE: ${{ secrets.MAVEN_GPG_PASSPHRASE }}
+
+  update-release-notes:
+    name: Update GitHub Release Notes
+    needs: release
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Generate and Update Release Notes
+        continue-on-error: true
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          CURRENT_TAG=${{ github.ref_name }}
+          VERSION_NUM=${CURRENT_TAG#v}
+
+          # Calculate previous tag using version sorting
+          git fetch --tags --force
+          PREV_TAG=$(git tag --sort=-v:refname | grep -A 1 "^${CURRENT_TAG}$" | tail -n 1)
+
+          # Fetch milestone ID for the link
+          MILESTONE_ID=$(gh api repos/${{ github.repository }}/milestones -q ".[] | select(.title==\"$VERSION_NUM\") | .number")
+
+          # Fetch closed issues and PRs for this milestone, excluding the dependencies label
+          gh issue list \
+            --repo ${{ github.repository }} \
+            --search "milestone:\"$VERSION_NUM\" is:closed -label:dependencies" \
+            --limit 100 \
+            --json title,url \
+            --jq '.[] | "- [\(.title)](\(.url))"' > milestone_issues.md
+
+          # Assemble the final changelog.md
+          cat << EOF > changelog.md
+          $(cat milestone_issues.md)
+
+          ## Changes
+          - [$CURRENT_TAG](https://github.com/jooby-project/jooby/tree/$CURRENT_TAG)
+          - [Issues](https://github.com/jooby-project/jooby/milestone/$MILESTONE_ID?closed=1)
+          - [Changelog](https://github.com/jooby-project/jooby/compare/$PREV_TAG...$CURRENT_TAG)
+          - [Dependencies](https://github.com/jooby-project/jooby/pulls?q=is%3Apr+label%3Adependencies+is%3Aclosed+milestone%3A$VERSION_NUM)
+
+          ## Support my work
+          - [Sponsor](https://github.com/sponsors/jknack)
+
+          ### Sponsors
+          - [@premium-minds](https://github.com/premium-minds)
+          - [@agentgt](https://github.com/agentgt)
+          - [@tipsy](https://github.com/tipsy)
+          EOF
+
+          # Overwrite the existing release notes
+          gh release edit $CURRENT_TAG --notes-file changelog.md