ci: add GitHub Actions workflow for building and publishing

This workflow:
- Builds container images using ko
- Publishes images to GitHub Container Registry on main branch pushes
- Publishes both container images and Helm charts on tag releases
- Only builds images (no push) for pull requests

Author: a-hilaly

.github/workflows/build-push-image.yaml

@@ -0,0 +1,79 @@
+name: Build and Publish
+
+on:
+  push:
+    branches: [ main ]
+    tags: [ 'v*' ]
+  pull_request:
+    branches: [ main ]
+
+env:
+  KO_DOCKER_REPO: ghcr.io/${{ github.repository }}/controller
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Go
+        uses: actions/setup-go@v4
+        with:
+          go-version: '1.23'
+
+      - name: Install Dependencies
+        run: |
+          go mod download
+          go install sigs.k8s.io/controller-tools/cmd/[email protected]
+          go install sigs.k8s.io/kustomize/kustomize/[email protected]
+          go install github.com/google/ko@latest
+
+      - name: Run tests
+        run: make test WHAT=unit
+
+      - name: Log in to GitHub Container Registry
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Set Release Version
+        run: |
+          if [[ $GITHUB_REF == refs/tags/v* ]]; then
+            # Trim the 'v' prefix from the tag
+            echo "RELEASE_VERSION=${GITHUB_REF#refs/tags/v}" >> $GITHUB_ENV
+          else
+            echo "RELEASE_VERSION=dev-$(git rev-parse --short HEAD)" >> $GITHUB_ENV
+          fi
+
+      # Build and push image on push to main
+      - name: Build and Push Image
+        if: github.event_name != 'pull_request'
+        run: |
+          make publish-image
+
+      # Build image only on PR
+      - name: Build Image (PR)
+        if: github.event_name == 'pull_request'
+        run: |
+          make build-image
+
+      # Push helm chart only on tag
+      - name: Package and Push Helm Chart
+        if: github.ref_type == 'tag'
+        run: |
+          echo "${{ secrets.GITHUB_TOKEN }}" | helm registry login ghcr.io -u ${{ github.actor }} --password-stdin
+          # Use sed compatible with Linux (GitHub Actions runners)
+          cp ./config/crd/bases/* helm/crds/
+          sed -i "s/tag: .*/tag: \"${RELEASE_VERSION}\"/" helm/values.yaml
+          sed -i "s/version: .*/version: ${RELEASE_VERSION}/" helm/Chart.yaml
+          sed -i "s/appVersion: .*/appVersion: \"${RELEASE_VERSION}\"/" helm/Chart.yaml
+          helm package helm
+          HELM_IMAGE=ghcr.io/${{ github.repository }} make publish-helm