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/semver/internal/identifiers.js

@@ -0,0 +1,25 @@
+'use strict'
+
+const numeric = /^[0-9]+$/
+const compareIdentifiers = (a, b) => {
+  const anum = numeric.test(a)
+  const bnum = numeric.test(b)
+
+  if (anum && bnum) {
+    a = +a
+    b = +b
+  }
+
+  return a === b ? 0
+    : (anum && !bnum) ? -1
+    : (bnum && !anum) ? 1
+    : a < b ? -1
+    : 1
+}
+
+const rcompareIdentifiers = (a, b) => compareIdentifiers(b, a)
+
+module.exports = {
+  compareIdentifiers,
+  rcompareIdentifiers,
+}