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>

frontends/studio/src/stores/interactions.ts

@@ -0,0 +1,74 @@
+import { atom, map, computed, onMount } from 'nanostores'
+import { createFetcherStore, createBlogMutatorStore } from './fetcher'
+import type { InteractionConfig } from '../types'
+
+const defaultConfig: InteractionConfig = {
+  comments_enabled: false,
+  reactions_enabled: false,
+  reaction_mode: 'emoji',
+  reaction_emojis: '👍,❤️,🎉,🚀',
+  upvote_icon: 'arrow',
+  reactions_require_auth: false,
+}
+
+export const $interactionsData = createFetcherStore<InteractionConfig>(['/api/studio/interaction-config'])
+
+export const $interactions = map<InteractionConfig>({ ...defaultConfig })
+export const $initialInteractions = atom<InteractionConfig | null>(null)
+
+export const $hasInteractionChanges = computed(
+  [$interactions, $initialInteractions],
+  (current, initial) => initial !== null && JSON.stringify(current) !== JSON.stringify(initial)
+)
+
+export const $changedInteractionFields = computed(
+  [$interactions, $initialInteractions],
+  (current, initial) => {
+    if (!initial) return []
+    const changes: string[] = []
+    const labels: Record<string, string> = {
+      comments_enabled: 'Comments',
+      reactions_enabled: 'Reactions',
+      reaction_mode: 'Reaction mode',
+      reaction_emojis: 'Emojis',
+      upvote_icon: 'Upvote icon',
+      reactions_require_auth: 'Auth required',
+    }
+    for (const key of Object.keys(current) as (keyof InteractionConfig)[]) {
+      if (current[key] !== initial[key]) {
+        changes.push(labels[key] || key)
+      }
+    }
+    return changes
+  }
+)
+
+onMount($interactionsData, () => {
+  $interactionsData.listen(({ data }) => {
+    if (data) {
+      const merged = { ...defaultConfig, ...data }
+      $interactions.set(merged)
+      $initialInteractions.set(merged)
+    }
+  })
+})
+
+export const $saveInteractions = createBlogMutatorStore<InteractionConfig>(
+  async ({ data: config }) => {
+    const previous = $initialInteractions.get()
+    $initialInteractions.set({ ...config })
+
+    const res = await fetch('/api/studio/interaction-config', {
+      method: 'PUT',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify(config),
+    })
+
+    if (!res.ok) {
+      $initialInteractions.set(previous)
+      throw new Error('Failed to save interactions')
+    }
+
+    return config
+  }
+)