feat: 人设模板系统、节点调度标签、pydantic-settings收敛、错误处理增强

新增persona_template表和CRUD API，BaseIndividualModel增加node_affinity和template_origin_id字段，
WorkerCluster支持多集群Ray资源调度，环境变量收敛到pydantic-settings统一校验，
数据库异常转换为结构化BusinessError/RetryableError，系统节点支持custom_system_prompt。

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

kilostar/api/platform/onebot.py

@@ -266,8 +266,10 @@ async def send_message(
     if not user_id and not group_id:
         raise ValueError("必须指定 user_id 或 group_id 之一")
 
-    base = base_url or os.environ.get("ONEBOT_HTTP_URL", "http://127.0.0.1:5700")
-    token = access_token or os.environ.get("ONEBOT_ACCESS_TOKEN")
+    from kilostar.utils.settings import get_settings
+    _ob = get_settings().onebot
+    base = base_url or _ob.onebot_http_url
+    token = access_token or _ob.onebot_access_token or None
 
     if group_id:
         action = "send_group_msg"