Add GitHub Actions CI workflow

Author: gmlarumbe

.github/workflows/ci.yml

@@ -0,0 +1,19 @@
+name: CI
+on:
+  workflow_dispatch:
+  pull_request:
+  push:
+
+jobs:
+  test:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: true
+      matrix:
+        os: [ubuntu-latest, macos-latest] # windows-latest still not supported by tree-sitter/setup-action@v1
+    steps:
+      - uses: actions/checkout@v4
+      - uses: tree-sitter/setup-action@v1
+      - run: tree-sitter generate
+      - run: tree-sitter test
+