Add a release workflow

.github/workflows/release.yml

@@ -0,0 +1,58 @@
+name: Release
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: "Release version (e.g., 8.1.0)"
+        required: true
+        type: string
+
+permissions: {}
+
+jobs:
+  release:
+    name: Release
+    runs-on: ubuntu-latest
+    environment: release
+    permissions:
+      contents: write
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+
+      - name: Validate version
+        env:
+          VERSION: ${{ inputs.version }}
+        run: |
+          if [[ ! "$VERSION" =~ ^[0-9]+\.[0-9]+\.[0-9]+(-[a-zA-Z0-9.]+)?$ ]]; then
+            echo "::error::Version must match MAJOR.MINOR.PATCH (e.g., 8.1.0)"
+            exit 1
+          fi
+
+      - name: Publish release
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          TAG: v${{ inputs.version }}
+        run: |
+          RELEASE_JSON=$(gh release view "$TAG" --json isDraft,targetCommitish 2>&1) || {
+            echo "::error::No release found for $TAG"
+            exit 1
+          }
+
+          IS_DRAFT=$(echo "$RELEASE_JSON" | jq -r '.isDraft')
+          TARGET=$(echo "$RELEASE_JSON" | jq -r '.targetCommitish')
+
+          if [[ "$IS_DRAFT" != "true" ]]; then
+            echo "::error::Release $TAG already exists and is not a draft"
+            exit 1
+          fi
+
+          if [[ "$TARGET" != "$GITHUB_SHA" ]]; then
+            echo "::error::Draft release target ($TARGET) does not match current commit ($GITHUB_SHA)"
+            exit 1
+          fi
+
+          echo "Publishing draft release $TAG"
+          gh release edit "$TAG" --draft=false