refactor: move studio to frontends workspace

- Move studio from root to frontends/studio/
- Add owner-tools frontend for live blog admin UI
- Add shared ui component library
- Set up npm workspaces for frontends
- Add enhanced code block extension for editor

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

studio/vite.config.ts

@@ -1,47 +0,0 @@
-import { defineConfig } from 'vite'
-import react from '@vitejs/plugin-react'
-import UnoCSS from 'unocss/vite'
-
-export default defineConfig(({ command }) => ({
-  plugins: [UnoCSS(), react()],
-  base: '/studio',
-  build: {
-    outDir: 'dist',
-  },
-  optimizeDeps: {
-    include: [
-      // Pre-bundle heavy Tiptap dependencies
-      '@tiptap/react',
-      '@tiptap/starter-kit',
-      '@tiptap/extension-link',
-      '@tiptap/extension-image',
-      '@tiptap/extension-placeholder',
-      '@tiptap/extension-table',
-      '@tiptap/extension-task-list',
-      '@tiptap/extension-task-item',
-      '@tiptap/extension-code-block-lowlight',
-      '@tiptap/markdown',
-      'lowlight',
-      // Monaco editor
-      '@monaco-editor/react',
-    ],
-  },
-  ...(command === 'serve' && {
-    server: {
-      host: true,
-      strictPort: true,
-      allowedHosts: true,
-      hmr: {
-        clientPort: 80,
-        path: '/studio',
-      },
-      warmup: {
-        clientFiles: [
-          './src/components/editor/PostEditor.tsx',
-          './src/components/editor/SourceEditor.tsx',
-          './src/pages/PostEditorPage.tsx',
-        ],
-      },
-    },
-  }),
-}))