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-plugin-jsx-a11y/lib/util/getComputedRole.js

@@ -0,0 +1,19 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports["default"] = getComputedRole;
+var _getExplicitRole = _interopRequireDefault(require("./getExplicitRole"));
+var _getImplicitRole = _interopRequireDefault(require("./getImplicitRole"));
+function _interopRequireDefault(e) { return e && e.__esModule ? e : { "default": e }; }
+/**
+ * Returns an element's computed role, which is
+ *
+ *  1. The valid value of its explicit role attribute; or
+ *  2. The implicit value of its tag.
+ */
+function getComputedRole(tag, attributes) {
+  return (0, _getExplicitRole["default"])(tag, attributes) || (0, _getImplicitRole["default"])(tag, attributes);
+}
+module.exports = exports.default;