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/aria-query/lib/etc/roles/literal/emphasisRole.js

@@ -0,0 +1,28 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.default = void 0;
+var emphasisRole = {
+  abstract: false,
+  accessibleNameRequired: false,
+  baseConcepts: [],
+  childrenPresentational: false,
+  nameFrom: ['prohibited'],
+  prohibitedProps: ['aria-label', 'aria-labelledby'],
+  props: {},
+  relatedConcepts: [{
+    concept: {
+      name: 'em'
+    },
+    module: 'HTML'
+  }],
+  requireContextRole: [],
+  requiredContextRole: [],
+  requiredOwnedElements: [],
+  requiredProps: {},
+  superClass: [['roletype', 'structure', 'section']]
+};
+var _default = emphasisRole;
+exports.default = _default;