Add CI test workflow + mark playground JS as linguist-generated for correct language stats

Author: Dale-Black

.gitattributes

@@ -0,0 +1,7 @@
+# Mark playground JS files as generated so GitHub language stats
+# correctly show this as a Julia package, not a JavaScript project.
+# These files ARE source code (hand-written), but they're runtime
+# artifacts for the browser playground, not the package's core logic.
+src/playground/*.js linguist-generated=true
+docs/src/assets/playground/*.js linguist-generated=true
+docs/playground/*.html linguist-generated=true

.github/workflows/ci.yml

@@ -0,0 +1,42 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+jobs:
+  test:
+    name: Julia ${{ matrix.version }} - ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        version:
+          - '1.12'
+        os:
+          - ubuntu-latest
+          - macos-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: julia-actions/setup-julia@v2
+        with:
+          version: ${{ matrix.version }}
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+
+      - uses: julia-actions/cache@v2
+
+      - name: Install dependencies
+        run: |
+          julia --project=. -e '
+            using Pkg
+            Pkg.instantiate()
+          '
+
+      - name: Run tests
+        run: |
+          julia --project=. test/runtests.jl