ci: configure semantic-release for automated releases

Adds a configuration for semantic-release bot matching the existing tag
structure and integrates releases in the CI process.

.github/workflows/release.yml

@@ -15,3 +15,61 @@ jobs:
         with:
           fetch-depth: 0
       - uses: wagoid/commitlint-github-action@v5
+
+  test-release:
+    name: Dry-run semantic-release
+    runs-on: ubuntu-latest
+    if: ${{ github.event_name == 'pull_request' }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+      - name: Checkout branch
+        # Pretend to semantic-release that the PR result is eligible for
+        # building releases because --dry-run still filters for configured
+        # branches.
+        run: git checkout -b main
+      - name: Setup Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: 18
+      - name: Cache Node packages
+        uses: actions/cache@v3
+        with:
+          path: node_modules
+          key: release-${{ hashFiles('package.json') }}-${{ hashFiles('package-lock.json') }}
+      - name: Install dependencies
+        run: npm ci
+      - name: Dry-run release
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        # We need to convince semantic-release to not pick up some
+        # configuration from the CI environment by removing the variable that
+        # is used for CI detection.
+        run: unset GITHUB_ACTIONS && npx semantic-release --dry-run --ci false
+
+  release:
+    name: Run semantic release
+    runs-on: ubuntu-latest
+    if: ${{ github.ref == 'refs/heads/main' }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+      - name: Setup Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: 18
+      - name: Cache Node packages
+        uses: actions/cache@v3
+        with:
+          path: node_modules
+          key: release-${{ hashFiles('package.json') }}-${{ hashFiles('package-lock.json') }}
+      - name: Install dependencies
+        run: npm ci
+      - name: Release
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: npx semantic-release

.releaserc.json

@@ -0,0 +1,21 @@
+{
+  "branches": [
+    "main"
+  ],
+  "tagFormat": "${version}",
+  "plugins": [
+    [
+      "@semantic-release/commit-analyzer",
+      {
+        "preset": "conventionalcommits"
+      }
+    ],
+    [
+      "@semantic-release/release-notes-generator",
+      {
+        "preset": "angular"
+      }
+    ],
+    "@semantic-release/github"
+  ]
+}