Initial commit: Nextcloud Notes Tauri app with WYSIWYG editor

Features:
- WYSIWYG markdown editor with TipTap
- Manual save with unsaved changes indicator
- Auto-title derivation from first line (with manual override)
- Manual sync button with visual feedback
- Auto-sync every 5 minutes
- Full formatting toolbar (bold, italic, headings, lists, code)
- Note creation, editing, deletion
- Search and favorites filter
- Cross-platform desktop app built with Tauri + React + TypeScript

src/main.tsx

@@ -0,0 +1,10 @@
+import React from "react";
+import ReactDOM from "react-dom/client";
+import App from "./App";
+import "./index.css";
+
+ReactDOM.createRoot(document.getElementById("root") as HTMLElement).render(
+  <React.StrictMode>
+    <App />
+  </React.StrictMode>,
+);