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/eslint-module-utils/declaredScope.js

@@ -0,0 +1,13 @@
+'use strict';
+
+exports.__esModule = true;
+
+const { getScope } = require('./contextCompat');
+
+/** @type {import('./declaredScope').default} */
+exports.default = function declaredScope(context, name, node) {
+  const references = (node ? getScope(context, node) : context.getScope()).references;
+  const reference = references.find((x) => x.identifier.name === name);
+  if (!reference || !reference.resolved) { return undefined; }
+  return reference.resolved.scope.type;
+};