ci: add luacheck workflow

Author: haithium

.github/laucheck.yml

@@ -0,0 +1,14 @@
+name: Luacheck
+
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - "**/*.lua"
+      - ".github/workflows/luacheck.yml"
+  workflow_dispatch:
+
+jobs:
+  luacheck:
+    uses: BlueLua/bluelua.github.io/.github/workflows/luacheck.yml@main