chore: add .xlings.json for environment setup

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Sunrisepeak

.xlings.json

@@ -0,0 +1,7 @@
+{
+  "workspace": {
+    "xmake": "3.0.7",
+    "gcc": { "linux": "15.1.0" },
+    "llvm": { "macosx": "20" }
+  }
+}