feat: Complete internationalization and code cleanup

## Translation Files
- Add 11 new language files (es, de, pt, ru, zh, ja, ko, ar, hi, nl, pl)
- Add 100+ missing translation keys across all 15 languages
- New sections: notebook, pagination, ai.batchOrganization, ai.autoLabels
- Update nav section with workspace, quickAccess, myLibrary keys

## Component Updates
- Update 15+ components to use translation keys instead of hardcoded text
- Components: notebook dialogs, sidebar, header, note-input, ghost-tags, etc.
- Replace 80+ hardcoded English/French strings with t() calls
- Ensure consistent UI across all supported languages

## Code Quality
- Remove 77+ console.log statements from codebase
- Clean up API routes, components, hooks, and services
- Keep only essential error handling (no debugging logs)

## UI/UX Improvements
- Update Keep logo to yellow post-it style (from-yellow-400 to-amber-500)
- Change selection colors to #FEF3C6 (notebooks) and #EFB162 (nav items)
- Make "+" button permanently visible in notebooks section
- Fix grammar and syntax errors in multiple components

## Bug Fixes
- Fix JSON syntax errors in it.json, nl.json, pl.json, zh.json
- Fix syntax errors in notebook-suggestion-toast.tsx
- Fix syntax errors in use-auto-tagging.ts
- Fix syntax errors in paragraph-refactor.service.ts
- Fix duplicate "fusion" section in nl.json

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Ou une version plus courte si vous préférez :

feat(i18n): Add 15 languages, remove logs, update UI components

- Create 11 new translation files (es, de, pt, ru, zh, ja, ko, ar, hi, nl, pl)
- Add 100+ translation keys: notebook, pagination, AI features
- Update 15+ components to use translations (80+ strings)
- Remove 77+ console.log statements from codebase
- Fix JSON syntax errors in 4 translation files
- Fix component syntax errors (toast, hooks, services)
- Update logo to yellow post-it style
- Change selection colors (#FEF3C6, #EFB162)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

keep-notes/hooks/use-title-suggestions.ts

@@ -0,0 +1,74 @@
+import { useState, useEffect } from 'react'
+import { useDebounce } from './use-debounce'
+
+export interface TitleSuggestion {
+  title: string
+  confidence: number
+  reasoning?: string
+}
+
+interface UseTitleSuggestionsProps {
+  content: string
+  enabled?: boolean
+}
+
+export function useTitleSuggestions({ content, enabled = true }: UseTitleSuggestionsProps) {
+  const [suggestions, setSuggestions] = useState<TitleSuggestion[]>([])
+  const [isAnalyzing, setIsAnalyzing] = useState(false)
+  const [error, setError] = useState<string | null>(null)
+
+  // Debounce le contenu de 2s pour éviter trop d'appels
+  const debouncedContent = useDebounce(content, 2000)
+
+  useEffect(() => {
+    if (!enabled || !debouncedContent) {
+      setSuggestions([])
+      return
+    }
+
+    const wordCount = debouncedContent.split(/\s+/).length
+
+    // Il faut au moins 10 mots
+    if (wordCount < 10) {
+      setSuggestions([])
+      return
+    }
+
+
+    const generateTitles = async () => {
+      setIsAnalyzing(true)
+      setError(null)
+
+      try {
+        const response = await fetch('/api/ai/title-suggestions', {
+          method: 'POST',
+          headers: { 'Content-Type': 'application/json' },
+          body: JSON.stringify({ content: debouncedContent }),
+        })
+
+
+        if (!response.ok) {
+          const errorData = await response.json()
+          throw new Error(errorData.error || 'Erreur lors de la génération des titres')
+        }
+
+        const data = await response.json()
+        setSuggestions(data.suggestions || [])
+      } catch (err) {
+        console.error('❌ Title suggestions error:', err)
+        setError('Impossible de générer des suggestions de titres')
+      } finally {
+        setIsAnalyzing(false)
+      }
+    }
+
+    generateTitles()
+  }, [debouncedContent, enabled])
+
+  return {
+    suggestions,
+    isAnalyzing,
+    error,
+    clearSuggestions: () => setSuggestions([])
+  }
+}