feat: add development scripts and CHANGELOG for v3.0.0

- Add typecheck script for TypeScript validation
- Add format and format:check scripts for code formatting
- Create comprehensive CHANGELOG documenting migration from Electron to Tauri
- Document all major changes, improvements, and migration notes for v3.0.0

package.json

@@ -7,7 +7,10 @@
     "build": "pnpm tauri build",
     "tauri": "tauri",
     "dev:renderer": "vite",
-    "build:renderer": "vite build"
+    "build:renderer": "vite build",
+    "typecheck": "tsc --noEmit",
+    "format": "prettier --write \"src/**/*.{js,jsx,ts,tsx,css,json}\"",
+    "format:check": "prettier --check \"src/**/*.{js,jsx,ts,tsx,css,json}\""
   },
   "keywords": [],
   "author": "Jason Young",