Add GitHub Actions release workflow

.github/workflows/release.yml

@@ -0,0 +1,58 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+permissions:
+  contents: write
+
+jobs:
+  release:
+    name: Build & publish plugin zip
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build plugin zip
+        working-directory: ${{ github.workspace }}
+        run: |
+          set -euo pipefail
+          VERSION="${GITHUB_REF_NAME#v}"
+          STAGE="dist/staging"
+          OUT="dist/projects-portfolio-v${VERSION}.zip"
+
+          rm -rf dist
+          mkdir -p "$STAGE/projects-portfolio"
+
+          cp projects-portfolio.php "$STAGE/projects-portfolio/"
+          cp README.md             "$STAGE/projects-portfolio/"
+          cp LICENSE               "$STAGE/projects-portfolio/"
+          cp -r admin/             "$STAGE/projects-portfolio/"
+          cp -r assets/            "$STAGE/projects-portfolio/"
+          cp -r includes/          "$STAGE/projects-portfolio/"
+          cp -r languages/         "$STAGE/projects-portfolio/"
+          cp -r templates/         "$STAGE/projects-portfolio/"
+
+          ( cd "$STAGE" && zip -r "../../$OUT" projects-portfolio )
+
+          echo "Built $OUT"
+          unzip -l "$OUT"
+
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: projects-portfolio-v${{ github.ref_name }}
+          path: dist/projects-portfolio-*.zip
+          if-no-files-found: error
+
+      - name: Create GitHub release
+        uses: softprops/action-gh-release@v2
+        with:
+          tag_name: ${{ github.ref_name }}
+          name: ${{ github.ref_name }}
+          generate_release_notes: true
+          files: dist/projects-portfolio-*.zip