feat: add system tools and state updates

frontend/src/lib/api.ts

@@ -216,6 +216,12 @@ export type StartupConfig = {
   } | null;
 };
 
+export type SystemToolKind =
+  | "end_conversation"
+  | "update_state"
+  | "skip_turn"
+  | "request_human_handoff";
+
 /** 后端 AssistantOut(宽表 STI:瘦字段平铺,workflow 用 graph)。apiKey 读时打码 */
 export type Assistant = {
   id: string;
@@ -226,6 +232,7 @@ export type Assistant = {
   enableInterrupt: boolean;
   turnConfig: TurnConfig;
   startup: StartupConfig;
+  systemTools: SystemToolKind[];
   visionEnabled: boolean;
   visionModelResourceId: string | null;
   modelResourceIds: Partial<Record<ModelType, string>>;
@@ -354,10 +361,11 @@ export type ToolParameter = {
   required: boolean;
 };
 
-export type EndCallToolDefinition = {
+export type SystemToolDefinition = {
   schemaVersion: number;
-  type: "end_call";
+  type: "system";
   config: {
+    kind: "end_conversation";
     messageType: "none" | "custom";
     customMessage: string;
     captureReason: boolean;
@@ -411,10 +419,10 @@ export type Tool = {
   id: string;
   name: string;
   functionName: string;
-  type: "end_call" | "http" | "mcp" | "client";
+  type: "system" | "http" | "mcp" | "client";
   description: string;
   definition:
-    | EndCallToolDefinition
+    | SystemToolDefinition
     | HttpToolDefinition
     | ClientToolDefinition
     | McpToolDefinition;