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/adjust-sourcemap-loader/lib/process/to-reg-exp.js

@@ -0,0 +1,19 @@
+'use strict';
+
+var regexParser = require('regex-parser');
+
+var REGEXP = /(\/?)(.+)\1([a-z]*)/i;
+
+/**
+ * Parse the give value as a regular expression or give a pass-none expression where it is invalid
+ * @param {RegExp|string|*} value An existing expression, or its string representation, or degenerate value
+ * @returns {RegExp} The given expression or one matching the RegExp string else a pass-none expression
+ */
+function toRegExp(value) {
+  return ((typeof value === 'object') && (typeof value.test === 'function') && value) ||
+    ((typeof value === 'string') && REGEXP.test(value) && regexParser(value)) ||
+    (/^true$|^$/.test(value) && /.*/) ||
+    /matchnone^/;
+}
+
+module.exports = toRegExp;