Move CI/CD from GitLab to GitHub Actions

- Add ci.yml for lint/test/build on push and PRs
- Update release workflow with CI gate before release and publish
- Publishing now runs via GitHub Actions (free for public repos)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Jennifer Brehm

.github/workflows/ci.yml

@@ -0,0 +1,17 @@
+name: CI
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+jobs:
+  ci:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          components: clippy
+      - run: cargo clippy -- -D warnings
+      - run: cargo test
+      - run: cargo build --release

.github/workflows/github-release.yml

@@ -1,21 +1,32 @@
-name: Create GitHub Release
-
+name: Release and Publish
 on:
   push:
-    tags:
-      - 'v*'
-
+    tags: ['v*']
 permissions:
   contents: write
-
 jobs:
+  ci:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+      - run: cargo test
+      - run: cargo build --release
   release:
     runs-on: ubuntu-latest
+    needs: ci
+    permissions:
+      contents: write
     steps:
-      - name: Checkout code
-        uses: actions/checkout@v4
-
-      - name: Create Release
-        uses: softprops/action-gh-release@v2
+      - uses: actions/checkout@v4
+      - uses: softprops/action-gh-release@v2
         with:
           generate_release_notes: true
+  publish:
+    runs-on: ubuntu-latest
+    needs: ci
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+      - name: Publish to crates.io
+        run: cargo publish --token ${{ secrets.CARGO_REGISTRY_TOKEN }}