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-tauri/capabilities/default.json

@@ -0,0 +1,10 @@
+{
+  "$schema": "../gen/schemas/desktop-schema.json",
+  "identifier": "default",
+  "description": "Capability for the main window",
+  "windows": ["main"],
+  "permissions": [
+    "core:default",
+    "opener:default"
+  ]
+}