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/loader-utils/lib/urlToRequest.js

@@ -0,0 +1,60 @@
+'use strict';
+
+// we can't use path.win32.isAbsolute because it also matches paths starting with a forward slash
+const matchNativeWin32Path = /^[A-Z]:[/\\]|^\\\\/i;
+
+function urlToRequest(url, root) {
+  // Do not rewrite an empty url
+  if (url === '') {
+    return '';
+  }
+
+  const moduleRequestRegex = /^[^?]*~/;
+  let request;
+
+  if (matchNativeWin32Path.test(url)) {
+    // absolute windows path, keep it
+    request = url;
+  } else if (root !== undefined && root !== false && /^\//.test(url)) {
+    // if root is set and the url is root-relative
+    switch (typeof root) {
+      // 1. root is a string: root is prefixed to the url
+      case 'string':
+        // special case: `~` roots convert to module request
+        if (moduleRequestRegex.test(root)) {
+          request = root.replace(/([^~/])$/, '$1/') + url.slice(1);
+        } else {
+          request = root + url;
+        }
+        break;
+      // 2. root is `true`: absolute paths are allowed
+      //    *nix only, windows-style absolute paths are always allowed as they doesn't start with a `/`
+      case 'boolean':
+        request = url;
+        break;
+      default:
+        throw new Error(
+          "Unexpected parameters to loader-utils 'urlToRequest': url = " +
+            url +
+            ', root = ' +
+            root +
+            '.'
+        );
+    }
+  } else if (/^\.\.?\//.test(url)) {
+    // A relative url stays
+    request = url;
+  } else {
+    // every other url is threaded like a relative url
+    request = './' + url;
+  }
+
+  // A `~` makes the url an module
+  if (moduleRequestRegex.test(request)) {
+    request = request.replace(moduleRequestRegex, '');
+  }
+
+  return request;
+}
+
+module.exports = urlToRequest;