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/components/collaborator-avatars.tsx

@@ -3,6 +3,7 @@
 import { Avatar, AvatarFallback, AvatarImage } from '@/components/ui/avatar'
 import { Badge } from '@/components/ui/badge'
 import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from '@/components/ui/tooltip'
+import { useLanguage } from '@/lib/i18n'
 
 interface Collaborator {
   id: string
@@ -18,6 +19,8 @@ interface CollaboratorAvatarsProps {
 }
 
 export function CollaboratorAvatars({ collaborators, ownerId, maxDisplay = 5 }: CollaboratorAvatarsProps) {
+  const { t } = useLanguage()
+
   if (collaborators.length === 0) return null
 
   const displayCollaborators = collaborators.slice(0, maxDisplay)
@@ -39,14 +42,14 @@ export function CollaboratorAvatars({ collaborators, ownerId, maxDisplay = 5 }:
                 {collaborator.id === ownerId && (
                   <div className="absolute -bottom-1 -right-1">
                     <Badge variant="secondary" className="text-[8px] h-3 px-1 min-w-0">
-                      Owner
+                      {t('collaboration.owner')}
                     </Badge>
                   </div>
                 )}
               </div>
             </TooltipTrigger>
             <TooltipContent>
-              <p className="font-medium">{collaborator.name || 'Unnamed User'}</p>
+              <p className="font-medium">{collaborator.name || t('collaboration.unnamedUser')}</p>
               <p className="text-xs text-muted-foreground">{collaborator.email}</p>
             </TooltipContent>
           </Tooltip>
@@ -60,7 +63,7 @@ export function CollaboratorAvatars({ collaborators, ownerId, maxDisplay = 5 }:
               </div>
             </TooltipTrigger>
             <TooltipContent>
-              <p>{remainingCount} more collaborator{remainingCount > 1 ? 's' : ''}</p>
+              <p>{remainingCount} {t('collaboration.canEdit')}</p>
             </TooltipContent>
           </Tooltip>
         )}