Add WebLLM support, fix progress bar blocking at 90%, add timeout protection

services/translation_service.py

@@ -139,6 +139,16 @@ class OllamaTranslationProvider(TranslationProvider):
             return []
 
 
+class WebLLMTranslationProvider(TranslationProvider):
+    """WebLLM browser-based translation (client-side processing)"""
+    
+    def translate(self, text: str, target_language: str, source_language: str = 'auto') -> str:
+        # WebLLM translation happens client-side in the browser
+        # This is just a placeholder - actual translation is done by JavaScript
+        # For server-side, we'll just pass through for now
+        return text
+
+
 class TranslationService:
     """Main translation service that delegates to the configured provider"""