[split-required] Split website + studio-v2 monoliths (Phase 3 continued)

Website (14 monoliths split):
- compliance/page.tsx (1,519 → 9), docs/audit (1,262 → 20)
- quality (1,231 → 16), alerts (1,203 → 10), docs (1,202 → 11)
- i18n.ts (1,173 → 8 language files)
- unity-bridge (1,094 → 12), backlog (1,087 → 6)
- training (1,066 → 8), rag (1,063 → 8)
- Deleted index_original.ts (4,899 LOC dead backup)

Studio-v2 (5 monoliths split):
- meet/page.tsx (1,481 → 9), messages (1,166 → 9)
- AlertsB2BContext.tsx (1,165 → 5 modules)
- alerts-b2b/page.tsx (1,019 → 6), korrektur/archiv (1,001 → 6)

All existing imports preserved. Zero new TypeScript errors.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

website/app/admin/backlog/_components/useBacklog.ts

@@ -0,0 +1,110 @@
+'use client'
+
+import { useState, useEffect } from 'react'
+import type { BacklogItem } from './types'
+import { initialBacklogItems } from './backlogData'
+import { categories } from './categories'
+
+export function useBacklog() {
+  const [items, setItems] = useState<BacklogItem[]>(initialBacklogItems)
+  const [selectedCategory, setSelectedCategory] = useState<string | null>(null)
+  const [selectedPriority, setSelectedPriority] = useState<string | null>(null)
+  const [expandedItems, setExpandedItems] = useState<Set<string>>(new Set())
+  const [searchQuery, setSearchQuery] = useState('')
+
+  // Load saved state from localStorage
+  useEffect(() => {
+    const saved = localStorage.getItem('backlogItems')
+    if (saved) {
+      try {
+        setItems(JSON.parse(saved))
+      } catch (e) {
+        console.error('Failed to load backlog items:', e)
+      }
+    }
+  }, [])
+
+  // Save state to localStorage
+  useEffect(() => {
+    localStorage.setItem('backlogItems', JSON.stringify(items))
+  }, [items])
+
+  const filteredItems = items.filter((item) => {
+    if (selectedCategory && item.category !== selectedCategory) return false
+    if (selectedPriority && item.priority !== selectedPriority) return false
+    if (searchQuery) {
+      const query = searchQuery.toLowerCase()
+      return (
+        item.title.toLowerCase().includes(query) ||
+        item.description.toLowerCase().includes(query) ||
+        item.subtasks?.some((st) => st.title.toLowerCase().includes(query))
+      )
+    }
+    return true
+  })
+
+  const toggleExpand = (id: string) => {
+    const newExpanded = new Set(expandedItems)
+    if (newExpanded.has(id)) {
+      newExpanded.delete(id)
+    } else {
+      newExpanded.add(id)
+    }
+    setExpandedItems(newExpanded)
+  }
+
+  const updateItemStatus = (id: string, status: BacklogItem['status']) => {
+    setItems(items.map((item) => (item.id === id ? { ...item, status } : item)))
+  }
+
+  const toggleSubtask = (itemId: string, subtaskId: string) => {
+    setItems(
+      items.map((item) => {
+        if (item.id !== itemId) return item
+        return {
+          ...item,
+          subtasks: item.subtasks?.map((st) =>
+            st.id === subtaskId ? { ...st, completed: !st.completed } : st
+          ),
+        }
+      })
+    )
+  }
+
+  const getProgress = () => {
+    const total = items.length
+    const completed = items.filter((i) => i.status === 'completed').length
+    return { total, completed, percentage: Math.round((completed / total) * 100) }
+  }
+
+  const getCategoryProgress = (categoryId: string) => {
+    const categoryItems = items.filter((i) => i.category === categoryId)
+    const completed = categoryItems.filter((i) => i.status === 'completed').length
+    return { total: categoryItems.length, completed }
+  }
+
+  const clearFilters = () => {
+    setSelectedCategory(null)
+    setSelectedPriority(null)
+    setSearchQuery('')
+  }
+
+  return {
+    items,
+    filteredItems,
+    selectedCategory,
+    setSelectedCategory,
+    selectedPriority,
+    setSelectedPriority,
+    expandedItems,
+    searchQuery,
+    setSearchQuery,
+    toggleExpand,
+    updateItemStatus,
+    toggleSubtask,
+    getProgress,
+    getCategoryProgress,
+    clearFilters,
+    categories,
+  }
+}