Add GitHub Actions for CI and npm release

Release workflow publishes to npm on v* tags using npm Trusted
Publishing (OIDC) — no NPM_TOKEN secret needed. CI workflow runs
the bob build on pull requests and pushes to main.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: jaymaycry

.github/workflows/ci.yml

@@ -0,0 +1,26 @@
+name: CI
+
+on:
+  pull_request:
+  push:
+    branches: [main]
+
+jobs:
+  build:
+    name: Typecheck & build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+          cache: 'yarn'
+
+      - name: Install dependencies
+        run: yarn install --frozen-lockfile
+
+      - name: Build (bob)
+        run: yarn prepare

.github/workflows/release.yml

@@ -0,0 +1,46 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+permissions:
+  contents: read
+  id-token: write
+
+jobs:
+  publish:
+    name: Publish to npm
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+          registry-url: 'https://registry.npmjs.org'
+          cache: 'yarn'
+
+      - name: Install dependencies
+        run: yarn install --frozen-lockfile
+
+      - name: Verify tag matches package.json version
+        run: |
+          PKG_VERSION=$(node -p "require('./package.json').version")
+          TAG_VERSION="${GITHUB_REF_NAME#v}"
+          if [ "$PKG_VERSION" != "$TAG_VERSION" ]; then
+            echo "Tag $GITHUB_REF_NAME (version $TAG_VERSION) does not match package.json version $PKG_VERSION"
+            exit 1
+          fi
+
+      - name: Build
+        run: yarn prepare
+
+      - name: Upgrade npm (Trusted Publishing requires >= 11.5.1)
+        run: npm install -g npm@latest
+
+      - name: Publish
+        run: npm publish --access public