Initial commit: Developer Tools MVP with visual editor

- Complete React app with 7 developer tools
- JSON Tool with visual structured editor
- Serialize Tool with visual structured editor
- URL, Base64, CSV/JSON, Beautifier, Diff tools
- Responsive navigation with dropdown menu
- Dark/light mode toggle
- Mobile-responsive design with sticky header
- All tools working with copy/paste functionality

node_modules/@babel/helper-define-polyfill-provider/lib/browser/dependencies.js

@@ -0,0 +1,22 @@
+"use strict";
+
+exports.__esModule = true;
+exports.has = has;
+exports.laterLogMissing = laterLogMissing;
+exports.logMissing = logMissing;
+exports.resolve = resolve;
+function resolve(dirname, moduleName, absoluteImports) {
+  if (absoluteImports === false) return moduleName;
+  throw new Error(`"absoluteImports" is not supported in bundles prepared for the browser.`);
+}
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+function has(basedir, name) {
+  return true;
+}
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+function logMissing(missingDeps) {}
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+function laterLogMissing(missingDeps) {}