Add Publish to GitHub Packages workflow

.github/workflows/publish-github-packages.yml

@@ -0,0 +1,58 @@
+name: Publish to GitHub Packages
+
+on:
+  push:
+    tags:
+      - 'v*'   # Triggers on version tags like v1.0.0, v2.1.3, etc.
+  workflow_dispatch:  # Allows manual trigger from GitHub Actions UI
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up JDK
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: '21'    # Match the project's Java version requirement (buildSrc needs Java 21)
+
+      - name: Cache Gradle packages
+        uses: actions/cache@v4
+        with:
+          path: |
+            ~/.gradle/caches
+            ~/.gradle/wrapper
+          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+
+      - name: Grant execute permission for Gradle wrapper
+        run: chmod +x ./gradlew
+
+      # CONFIGURATION REQUIRED:
+      # The following step publishes to GitHub Packages using credentials.
+      # No additional setup is needed as the project already has:
+      # 1. maven-publish plugin configured in lib/build.gradle.kts
+      # 2. GitHub Packages repository configuration with proper URL
+      # 3. Authentication using USERNAME and TOKEN environment variables
+      # 
+      # The GITHUB_TOKEN is automatically provided by GitHub Actions and has
+      # the necessary permissions to publish packages to the same repository.
+      # 
+      # If you need to publish to a different repository's packages, you would need to:
+      # 1. Create a Personal Access Token (PAT) with 'write:packages' permission
+      # 2. Add it as a repository secret (e.g., PACKAGES_TOKEN)
+      # 3. Use that secret instead of GITHUB_TOKEN
+      #
+      # The current version is hardcoded in lib/build.gradle.kts as "1.0.0"
+      # For dynamic versioning, consider:
+      # 1. Using the git tag (${GITHUB_REF#refs/tags/})
+      # 2. Reading version from gradle.properties
+      # 3. Using a gradle plugin like 'axion-release-plugin'
+      - name: Publish to GitHub Packages
+        env:
+          USERNAME: ${{ github.actor }}        # GitHub username of the user/bot triggering the workflow
+          TOKEN: ${{ secrets.GITHUB_TOKEN }}   # GitHub token with packages:write permission
+        run: ./gradlew publish