feat: add devtools (tree-sitter, neovim, formatter, CLI commands)

- Add tree-sitter grammar for syntax highlighting
- Add Neovim plugin with syntax, LSP integration, and commands
- Add code formatter (lux fmt) with check mode
- Add CLI commands: fmt, check, test, watch, init
- Add project initialization with lux.toml template

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

editors/tree-sitter-lux/package.json

@@ -0,0 +1,38 @@
+{
+  "name": "tree-sitter-lux",
+  "version": "0.1.0",
+  "description": "Tree-sitter grammar for the Lux programming language",
+  "main": "bindings/node",
+  "keywords": [
+    "tree-sitter",
+    "parser",
+    "lux"
+  ],
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/your-org/lux"
+  },
+  "license": "MIT",
+  "dependencies": {
+    "nan": "^2.17.0"
+  },
+  "devDependencies": {
+    "tree-sitter-cli": "^0.20.8"
+  },
+  "scripts": {
+    "build": "tree-sitter generate && node-gyp rebuild",
+    "test": "tree-sitter test",
+    "parse": "tree-sitter parse"
+  },
+  "tree-sitter": [
+    {
+      "scope": "source.lux",
+      "injection-regex": "lux",
+      "file-types": [
+        "lux"
+      ],
+      "highlights": "queries/highlights.scm",
+      "locals": "queries/locals.scm"
+    }
+  ]
+}