feat: unify multimodels translation providers, remove self-hosting (Ollama/LibreTranslate), and fix local SQLite configuration

services/providers/base.py

@@ -73,6 +73,24 @@ class TranslationProvider(ABC):
         """
         return [self.translate_text(req) for req in requests]
 
+    def translate(
+        self, text: str, target_language: str, source_language: str = "auto"
+    ) -> str:
+        """
+        Compatibility method for the legacy interface.
+        Translates a single text string synchronously.
+        """
+        req = TranslationRequest(
+            text=text,
+            target_language=target_language,
+            source_language=source_language,
+        )
+        resp = self.translate_text(req)
+        if resp.error:
+            raise Exception(f"[{resp.error_code or 'UNKNOWN'}] {resp.error}")
+        return resp.translated_text
+
+
     def health_check(self) -> ProviderHealthStatus:
         """
         Return health status details for the provider.