Refactor assistant configuration and database seeding

- Update Makefile to include new database seed commands for assistants and credentials.
- Refactor assistant model to use explicit fields instead of a config dictionary, improving data integrity and clarity.
- Implement new seeding SQL script for assistants, ensuring dependencies on credentials are respected.
- Modify backend routes and frontend components to accommodate the new assistant structure, including direct field access for prompt, API URL, and keys.
- Enhance the AssistantPage component to handle the new data structure and streamline the save process for different assistant types.

backend/services/config_resolver.py

@@ -48,20 +48,18 @@ async def resolve_runtime_config(
     tts = await _resolve(session, assistant.tts_credential_id, "TTS")
     realtime = await _resolve(session, assistant.realtime_credential_id, "Realtime")
 
-    cfg = assistant.config or {}
-
     return AssistantConfig(
         name=assistant.name,
         greeting=assistant.greeting,
-        # 提示词/工作流类型把 prompt 放 config;外部类型由其平台编排,这里给个兜底
-        prompt=cfg.get("prompt") or "你是一个有帮助的助手。",
+        # prompt 现在是真列;外部类型由其平台编排,这里给个兜底
+        prompt=assistant.prompt or "你是一个有帮助的助手。",
         runtimeMode=assistant.runtime_mode,  # type: ignore[arg-type]
         enableInterrupt=assistant.enable_interrupt,
         # 模型/音色:凭证的模型ID优先
         model=(llm.model_id if llm else ""),
         asr=(stt.model_id if stt else ""),
-        voice=cfg.get("voice", ""),  # 音色不再是独立列,若 config 带则用,否则 .env 兜底
-        realtimeModel=(realtime.model_id if realtime else cfg.get("realtimeModel", "")),
+        voice="",  # 音色无独立列,留空 → service_factory 回退 .env TTS_VOICE
+        realtimeModel=(realtime.model_id if realtime else ""),
         # 运行时连接信息(真 key + url):凭证优先,否则 .env 兜底
         llm_api_key=(llm.api_key if llm else config.LLM_API_KEY),
         llm_base_url=(llm.api_url if llm else config.LLM_BASE_URL),