chore(deps): upgrade all dependencies to latest and migrate to Tailwind CSS v4

Resolves the open Dependabot PRs by upgrading every npm package to its
latest version and migrating the build to Tailwind CSS v4.

- Bump all runtime/dev deps to latest (Radix UI, better-auth, hono,
  react-hook-form, react-router-dom, recharts, resend, vite, wrangler,
  eslint, typescript-eslint, @types/node, etc.)
- commander 14 -> 15 (ESM-only); auth/db CLIs verified
- lucide-react 0.525 -> 1.x
- react-resizable-panels 3 -> 4: rewrite resizable.tsx for the renamed
  v4 API (Group/Panel/Separator, aria-orientation)
- Tailwind CSS v3 -> v4: @tailwindcss/postcss, CSS-first @theme config,
  swap tailwindcss-animate for tw-animate-css, scope content to src/react-app
- esbuild security advisory fixed transitively via Vite (0 vulnerabilities)
- ci: actions/checkout v6 -> v7
- remove git-tracked sublimewriter symlink

Author: claudio-silva

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
 
       - name: Setup Node.js
         uses: actions/setup-node@v6

components.json

@@ -4,7 +4,7 @@
   "rsc": false,
   "tsx": true,
   "tailwind": {
-    "config": "tailwind.config.js",
+    "config": "",
     "css": "src/react-app/index.css",
     "baseColor": "neutral",
     "cssVariables": true,