feat: initial Reaktor modular synth app

React + Tone.js modular synthesizer with visual node editor.
Includes: Oscillator, Filter, Envelope, LFO, VCA, Delay, Reverb,
Distortion, Mixer, Scope, Output, and Keyboard modules.
SVG wire connections, knob controls, preset save/load system.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/main.jsx

@@ -0,0 +1,6 @@
+import React from 'react';
+import { createRoot } from 'react-dom/client';
+import App from './App';
+import './index.css';
+
+createRoot(document.getElementById('root')).render(<App />);