chore: add luarc

Author: 3rd

.luarc.json

@@ -0,0 +1,9 @@
+{
+  "$schema": "https://raw.githubusercontent.com/sumneko/vscode-lua/master/setting/schema.json",
+  "Lua.diagnostics.globals": [
+    "vim"
+  ],
+  "runtime": {
+    "version": "LuaJIT"
+  }
+}