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/sucrase/dist/esm/util/removeMaybeImportAttributes.js

@@ -0,0 +1,22 @@
+import {ContextualKeyword} from "../parser/tokenizer/keywords";
+import {TokenType as tt} from "../parser/tokenizer/types";
+
+
+/**
+ * Starting at a potential `with` or (legacy) `assert` token, remove the import
+ * attributes if they exist.
+ */
+export function removeMaybeImportAttributes(tokens) {
+  if (
+    tokens.matches2(tt._with, tt.braceL) ||
+    (tokens.matches2(tt.name, tt.braceL) && tokens.matchesContextual(ContextualKeyword._assert))
+  ) {
+    // assert
+    tokens.removeToken();
+    // {
+    tokens.removeToken();
+    tokens.removeBalancedCode();
+    // }
+    tokens.removeToken();
+  }
+}