fix(settings): 调整MCP循环默认值

说明：
- 将 MCP 工具循环默认上限从 10 提升到 100，降低复杂任务误触发 loop exceeded 的概率。
- 前后端共用默认值常量，空值回退保持与设置默认一致。

操作：
- 已手动配置过最大循环次数的用户不会被覆盖。

Closes #104

Author: Licoy

src-tauri/crates/core/src/types.rs

@@ -10,6 +10,8 @@ where
     Option::<T>::deserialize(deserializer).map(Some)
 }
 
+pub const DEFAULT_MCP_TOOL_LOOP_MAX_ITERATIONS: u32 = 100;
+
 // === Provider System ===
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -847,7 +849,7 @@ impl Default for AppSettings {
             inherit_conversation_preferences_on_create: true,
             chat_stream_first_packet_timeout_secs: 180,
             chat_stream_idle_timeout_secs: 90,
-            mcp_tool_loop_max_iterations: 10,
+            mcp_tool_loop_max_iterations: DEFAULT_MCP_TOOL_LOOP_MAX_ITERATIONS,
             document_attachment_reading_enabled: false,
             show_image_models_in_model_selector: false,
             multi_model_display_mode: "tabs".to_string(),
@@ -907,9 +909,9 @@ mod app_settings_tests {
     }
 
     #[test]
-    fn mcp_tool_loop_max_iterations_defaults_to_10_and_roundtrips() {
+    fn mcp_tool_loop_max_iterations_defaults_to_100_and_roundtrips() {
         let settings = AppSettings::default();
-        assert_eq!(settings.mcp_tool_loop_max_iterations, 10);
+        assert_eq!(settings.mcp_tool_loop_max_iterations, 100);
 
         let settings: AppSettings = serde_json::from_value(json!({
             "mcp_tool_loop_max_iterations": 25
@@ -920,7 +922,7 @@ mod app_settings_tests {
 
         let settings: AppSettings =
             serde_json::from_value(json!({})).expect("settings should default missing fields");
-        assert_eq!(settings.mcp_tool_loop_max_iterations, 10);
+        assert_eq!(settings.mcp_tool_loop_max_iterations, 100);
     }
 
     #[test]

src-tauri/src/commands/conversations.rs

@@ -5170,7 +5170,7 @@ mod tests {
     #[test]
     fn mcp_tool_loop_limit_clamps_global_settings() {
         let mut settings = AppSettings::default();
-        assert_eq!(mcp_tool_loop_max_iterations_from_settings(&settings), 10);
+        assert_eq!(mcp_tool_loop_max_iterations_from_settings(&settings), 100);
 
         settings.mcp_tool_loop_max_iterations = 0;
         assert_eq!(mcp_tool_loop_max_iterations_from_settings(&settings), 1);

src/components/settings/ConversationSettings.tsx

@@ -1,6 +1,7 @@
 import { Divider, Input, InputNumber, Switch, theme } from 'antd';
 import { useTranslation } from 'react-i18next';
 import { useSettingsStore } from '@/stores';
+import { DEFAULT_MCP_TOOL_LOOP_MAX_ITERATIONS } from '@/types';
 import { SettingsGroup } from './SettingsGroup';
 import { SettingsSelect } from './SettingsSelect';
 
@@ -13,8 +14,10 @@ function normalizeTimeoutSeconds(value: number | string | null) {
 }
 
 function normalizeMcpToolLoopMaxIterations(value: number | string | null) {
-  const numericValue = typeof value === 'number' ? value : Number(value ?? 10);
-  if (!Number.isFinite(numericValue)) return 10;
+  const numericValue = typeof value === 'number'
+    ? value
+    : Number(value ?? DEFAULT_MCP_TOOL_LOOP_MAX_ITERATIONS);
+  if (!Number.isFinite(numericValue)) return DEFAULT_MCP_TOOL_LOOP_MAX_ITERATIONS;
   return Math.min(100, Math.max(1, Math.floor(numericValue)));
 }
 
@@ -219,7 +222,7 @@ export function ConversationSettings() {
             min={1}
             max={100}
             step={1}
-            value={settings.mcp_tool_loop_max_iterations ?? 10}
+            value={settings.mcp_tool_loop_max_iterations ?? DEFAULT_MCP_TOOL_LOOP_MAX_ITERATIONS}
             onChange={(value) => saveSettings({
               mcp_tool_loop_max_iterations: normalizeMcpToolLoopMaxIterations(value),
             })}

src/components/settings/__tests__/ConversationSettings.test.tsx

@@ -132,7 +132,7 @@ describe('ConversationSettings', () => {
       show_image_models_in_model_selector: false,
       chat_stream_first_packet_timeout_secs: 180,
       chat_stream_idle_timeout_secs: 90,
-      mcp_tool_loop_max_iterations: 10,
+      mcp_tool_loop_max_iterations: 100,
       chat_sidebar_collapsed: false,
     };
   });
@@ -230,7 +230,7 @@ describe('ConversationSettings', () => {
 
     fireEvent.change(screen.getByLabelText('MCP 工具调用最大轮次'), { target: { value: '' } });
     expect(mocks.saveSettings).toHaveBeenCalledWith({
-      mcp_tool_loop_max_iterations: 10,
+      mcp_tool_loop_max_iterations: 100,
     });
 
     fireEvent.change(screen.getByLabelText('MCP 工具调用最大轮次'), { target: { value: '1000' } });

src/stores/settingsStore.ts

@@ -1,6 +1,6 @@
 import { create } from 'zustand';
 import { invoke } from '@/lib/invoke';
-import type { AppSettings } from '@/types';
+import { DEFAULT_MCP_TOOL_LOOP_MAX_ITERATIONS, type AppSettings } from '@/types';
 import { DEFAULT_SHORTCUT_BINDINGS } from '@/lib/shortcuts';
 
 const DEFAULT_SETTINGS: AppSettings = {
@@ -89,7 +89,7 @@ const DEFAULT_SETTINGS: AppSettings = {
   inherit_conversation_preferences_on_create: true,
   chat_stream_first_packet_timeout_secs: 180,
   chat_stream_idle_timeout_secs: 90,
-  mcp_tool_loop_max_iterations: 10,
+  mcp_tool_loop_max_iterations: DEFAULT_MCP_TOOL_LOOP_MAX_ITERATIONS,
   document_attachment_reading_enabled: false,
   show_image_models_in_model_selector: false,
   multi_model_display_mode: 'tabs',

src/types/index.ts

@@ -456,6 +456,8 @@ export interface GatewaySettings {
 }
 
 // === Settings ===
+export const DEFAULT_MCP_TOOL_LOOP_MAX_ITERATIONS = 100;
+
 export interface AppSettings {
   language: string;
   theme_mode: string;
@@ -571,7 +573,7 @@ export interface AppSettings {
   chat_stream_first_packet_timeout_secs?: number;
   /** Timeout between chat stream packets in seconds. 0 disables. */
   chat_stream_idle_timeout_secs?: number;
-  /** Maximum provider/tool iterations in one MCP tool loop. Default: 10. */
+  /** Maximum provider/tool iterations in one MCP tool loop. Default: 100. */
   mcp_tool_loop_max_iterations?: number;
   /** Parse PDF/DOC/DOCX attachments and send extracted text to the model. Default: false */
   document_attachment_reading_enabled?: boolean;