ci: skip docs CI for flue-only PRs, add Flue CI workflow

.github/workflows/ci.yml

@@ -4,6 +4,8 @@ on:
   pull_request:
     branches:
       - production
+    paths-ignore:
+      - ".flue/**"
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}

.github/workflows/flue-ci.yml

@@ -0,0 +1,79 @@
+name: Flue CI
+
+on:
+  pull_request:
+    branches:
+      - production
+    paths:
+      - ".flue/**"
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  pre-build:
+    name: Pre Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out repo
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+
+      - name: Set up pnpm
+        uses: pnpm/action-setup@fc06bc1257f339d1d5d8b3a19a8cae5388b55320 # v5
+        with:
+          version: 11
+
+      - name: Set up node
+        uses: actions/setup-node@53b83947a5a98c8d113130e565377fae1a50d02f # v6
+        with:
+          node-version: 24.x
+          cache: pnpm
+          cache-dependency-path: .flue/pnpm-lock.yaml
+
+      - name: Install node_modules
+        run: pnpm install --frozen-lockfile
+        working-directory: .flue
+
+      - name: Typecheck
+        run: pnpm run typecheck
+        working-directory: .flue
+
+  build:
+    name: Build
+    needs: pre-build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out repo
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+
+      - name: Set up pnpm
+        uses: pnpm/action-setup@fc06bc1257f339d1d5d8b3a19a8cae5388b55320 # v5
+        with:
+          version: 11
+
+      - name: Set up node
+        uses: actions/setup-node@53b83947a5a98c8d113130e565377fae1a50d02f # v6
+        with:
+          node-version: 24.x
+          cache: pnpm
+          cache-dependency-path: .flue/pnpm-lock.yaml
+
+      - name: Install node_modules
+        run: pnpm install --frozen-lockfile
+        working-directory: .flue
+
+      - name: Build
+        run: pnpm run build
+        working-directory: .flue
+
+  post-build:
+    name: Post Build
+    needs: build
+    runs-on: ubuntu-latest
+    steps:
+      - name: No post-build checks yet
+        run: echo "No post-build checks for flue yet."