Add ASR interim results support in Assistant model and API

- Introduced `asr_interim_enabled` field in the Assistant model to control interim ASR results.
- Updated AssistantBase and AssistantUpdate schemas to include the new field.
- Modified the database schema to add the `asr_interim_enabled` column.
- Enhanced runtime metadata to reflect interim ASR settings.
- Updated API endpoints and tests to validate the new functionality.
- Adjusted documentation to include details about interim ASR results configuration.

engine/providers/factory/default.py

@@ -117,6 +117,7 @@ class DefaultRealtimeServiceFactory(RealtimeServiceFactory):
                 model=spec.model or self._DEFAULT_OPENAI_COMPATIBLE_ASR_MODEL,
                 sample_rate=spec.sample_rate,
                 language=spec.language,
+                enable_interim=spec.enable_interim,
                 interim_interval_ms=spec.interim_interval_ms,
                 min_audio_for_interim_ms=spec.min_audio_for_interim_ms,
                 on_transcript=spec.on_transcript,