add goreleaser & goreleaser workflow (#8)

.github/workflows/goreleaser.yml

@@ -0,0 +1,72 @@
+name: Release Automation
+
+on:
+  push:
+    tags:
+      - "v[0-9]+.[0-9]+.[0-9]+"
+
+concurrency: ci-release-automation
+
+permissions:
+  contents: read
+
+jobs:
+  goreleaser:
+    timeout-minutes: 60
+    outputs:
+      hashes: ${{ steps.hash.outputs.hashes }}
+    permissions:
+      contents: write # for goreleaser/goreleaser-action to create a GitHub release
+      packages: write # for goreleaser/goreleaser-action to publish docker images
+    runs-on: ubuntu-latest
+    env:
+      # Required for buildx on docker 19.x
+      DOCKER_CLI_EXPERIMENTAL: "enabled"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
+        with:
+          fetch-depth: 0
+      - uses: docker/setup-qemu-action@e81a89b1732b9c48d79cd809d8d81d79c4647a18 # v2
+      - uses: docker/setup-buildx-action@8c0edbc76e98fa90f69d9a2c020dcb50019dc325 # v2
+      - name: Set up Go
+        uses: actions/setup-go@f111f3307d8850f501ac008e886eec1fd1932a34
+        with:
+          go-version: 1.24
+          check-latest: true
+      - name: ghcr-login
+        uses: docker/login-action@dd4fa0671be5250ee6f50aedf4cb05514abda2c7 # v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Run GoReleaser
+        id: run-goreleaser
+        uses: goreleaser/goreleaser-action@286f3b13b1b49da4ac219696163fb8c1c93e1200 # v6.0.0
+        with:
+          distribution: goreleaser
+          version: "~> v2"
+          args: release --clean
+        env:
+          GITHUB_TOKEN: ${{ secrets.GORELEASER_GITHUB_TOKEN }}
+
+      - name: Generate subject
+        id: hash
+        env:
+          ARTIFACTS: "${{ steps.run-goreleaser.outputs.artifacts }}"
+        run: |
+          set -euo pipefail
+          checksum_file=$(echo "$ARTIFACTS" | jq -r '.[] | select (.type=="Checksum") | .path')
+          echo "hashes=$(cat $checksum_file | base64 -w0)" >> "$GITHUB_OUTPUT"
+  provenance:
+    needs: [goreleaser]
+    permissions:
+      actions: read # To read the workflow path.
+      id-token: write # To sign the provenance.
+      contents: write # To add assets to a release.
+    uses: slsa-framework/slsa-github-generator/.github/workflows/generator_generic_slsa3.yml@f7dd8c54c2067bafc12ca7a55595d5ee9b75204a # v2.1.0
+    with:
+      base64-subjects: "${{ needs.goreleaser.outputs.hashes }}"
+      upload-assets: true
+      private-repository: false