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/tests/test_backend_adapters.py

@@ -282,7 +282,7 @@ async def test_local_yaml_adapter_rejects_path_traversal_like_assistant_id(tmp_p
 
 
 @pytest.mark.asyncio
-async def test_local_yaml_translates_agent_schema_to_runtime_services(tmp_path):
+async def test_local_yaml_translates_agent_schema_with_asr_interim_flag(tmp_path):
     config_dir = tmp_path / "assistants"
     config_dir.mkdir(parents=True, exist_ok=True)
     (config_dir / "default.yaml").write_text(
@@ -305,6 +305,7 @@ async def test_local_yaml_translates_agent_schema_to_runtime_services(tmp_path):
                 "    model: asr-model",
                 "    api_key: sk-asr",
                 "    api_url: https://asr.example.com/v1/audio/transcriptions",
+                "    enable_interim: false",
                 "  duplex:",
                 "    system_prompt: You are test assistant",
             ]
@@ -321,4 +322,5 @@ async def test_local_yaml_translates_agent_schema_to_runtime_services(tmp_path):
     assert services.get("llm", {}).get("apiKey") == "sk-llm"
     assert services.get("tts", {}).get("apiKey") == "sk-tts"
     assert services.get("asr", {}).get("apiKey") == "sk-asr"
+    assert services.get("asr", {}).get("enableInterim") is False
     assert assistant.get("systemPrompt") == "You are test assistant"