refactor: restore root-level development workflow with enhanced tooling

- Add root package.json with development scripts and dependencies
- Move scripts/ from lib back to root for intuitive developer experience
- Clean lib/package.json to contain only runtime dependencies
- Add comprehensive justfile with cross-platform command shortcuts
- Update README.md with new development workflow instructions
- Maintain lib as clean, publishable package while enabling root-level commands

lib/package.json

@@ -14,12 +14,7 @@
     "build:only": "rollup -c",
     "copy:demo": "cp dist/insertr.js ../demo-site/insertr.js",
     "watch": "rollup -c -w",
-    "dev": "rollup -c -w",
-    "serve": "node scripts/dev.js serve",
-    "serve:about": "live-server ../demo-site --port=3000 --open=/about.html",
-    "check": "node scripts/dev.js check",
-    "demo": "node scripts/dev.js demo",
-    "build:all": "node scripts/build.js"
+    "dev": "rollup -c -w"
   },
   "keywords": [
     "cms",
@@ -32,7 +27,6 @@
   "devDependencies": {
     "@rollup/plugin-node-resolve": "^15.0.0",
     "@rollup/plugin-terser": "^0.4.0",
-    "live-server": "^1.2.2",
     "rollup": "^3.0.0"
   },
   "dependencies": {