feat(toolset): 工具系统重构为 toolset 统一管理，新增系统预置工具集

将工具管理从"agent 挂单个 tool"改为"agent 挂 toolset"模式：
- 三个系统预置工具集（system_basic/system_chat/system_workflow）入 DB
- 新增 send_file 工具（系统对话工具集）、修复 approval actor 调用 bug
- 后端 agent 加载全部走 toolset 链路，移除 load_tools_from_list
- 前端工具集中心卡片展示 + agent 配置改为 toolset 多选
- resource API 增加 category 过滤与系统 toolset 保护

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

kilostar/api/agent.py

@@ -35,7 +35,7 @@ class AgentRegister(BaseModel):
     provider_title: str
     model_id: str
     individual_name: str
-    tools: Optional[List[str]] = None
+    toolsets: Optional[List[str]] = None
     persona_id: Optional[str] = None
     display_name: Optional[str] = None
 
@@ -45,7 +45,7 @@ class AgentLocalRegister(BaseModel):
 
     path: str
     individual_name: str
-    tools: Optional[List[str]] = None
+    toolsets: Optional[List[str]] = None
 
 
 @agent_router.get("")
@@ -78,13 +78,15 @@ async def load_agent(
                 agent_register.individual_name,
                 agent_register.provider_title,
                 agent_register.model_id,
-                agent_register.tools,
+                agent_register.toolsets,
                 agent_register.persona_id,
                 agent_register.display_name,
             )
 
             scope = agent_register.individual_name
-            toolsets = await get_all_toolsets_for_scope(scope)
+            toolsets = await get_all_toolsets_for_scope(
+                scope, toolset_ids=agent_register.toolsets
+            )
 
             # Resolve persona system_prompt from DB
             persona_prompt = None
@@ -100,7 +102,6 @@ async def load_agent(
                         global_state_machine,
                         agent_register.provider_title,
                         agent_register.model_id,
-                        agent_register.tools,
                         toolsets,
                         accept_lang,
                         persona_prompt,
@@ -111,7 +112,6 @@ async def load_agent(
                         global_state_machine,
                         agent_register.provider_title,
                         agent_register.model_id,
-                        agent_register.tools,
                         toolsets,
                         accept_lang,
                         persona_prompt,
@@ -140,7 +140,7 @@ class WorkerIndividualCreate(BaseModel):
     output_template: dict
     bound_skill: Dict[str, List[str]]
     workspace: List[str]
-    tools: Optional[List[str]] = None
+    toolsets: Optional[List[str]] = None
     node_affinity: str = "cpu"
 
     @field_validator("node_affinity")
@@ -163,7 +163,7 @@ class WorkerIndividualUpdate(BaseModel):
     output_template: Optional[dict] = None
     bound_skill: Optional[Dict[str, List[str]]] = None
     workspace: Optional[List[str]] = None
-    tools: Optional[List[str]] = None
+    toolsets: Optional[List[str]] = None
     node_affinity: Optional[str] = None
 
     @field_validator("node_affinity")