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/lib/ai/providers/openrouter.ts

@@ -1,7 +1,7 @@
 import { createOpenAI } from '@ai-sdk/openai';
-import { generateObject, embed } from 'ai';
+import { generateObject, generateText, embed } from 'ai';
 import { z } from 'zod';
-import { AIProvider, TagSuggestion } from '../types';
+import { AIProvider, TagSuggestion, TitleSuggestion } from '../types';
 
 export class OpenRouterProvider implements AIProvider {
   private model: any;
@@ -51,4 +51,38 @@ export class OpenRouterProvider implements AIProvider {
       return [];
     }
   }
+
+  async generateTitles(prompt: string): Promise<TitleSuggestion[]> {
+    try {
+      const { object } = await generateObject({
+        model: this.model,
+        schema: z.object({
+          titles: z.array(z.object({
+            title: z.string().describe('Le titre suggéré'),
+            confidence: z.number().min(0).max(1).describe('Le niveau de confiance entre 0 et 1')
+          }))
+        }),
+        prompt: prompt,
+      });
+
+      return object.titles;
+    } catch (e) {
+      console.error('Erreur génération titres OpenRouter:', e);
+      return [];
+    }
+  }
+
+  async generateText(prompt: string): Promise<string> {
+    try {
+      const { text } = await generateText({
+        model: this.model,
+        prompt: prompt,
+      });
+
+      return text.trim();
+    } catch (e) {
+      console.error('Erreur génération texte OpenRouter:', e);
+      throw e;
+    }
+  }
 }