feat: add MCP server support for AI agents

Add Model Context Protocol (MCP) server integration to extend AI agent
capabilities with external tools. This allows users to configure MCP
servers (stdio, SSE, HTTP) in global settings and have agents use them.

Note: MCP servers are currently configured globally. Per-project MCP
server configuration is planned for a future update.

Features:
- New MCP Servers settings section with full CRUD operations
- Import/Export JSON configs (Claude Code format compatible)
- Configurable permission settings:
  - Auto-approve MCP tools (bypass permission prompts)
  - Unrestricted tools (allow all tools when MCP enabled)
- Refresh button to reload from settings file

Implementation:
- Added MCPServerConfig and MCPToolInfo types
- Added store actions for MCP server management
- Updated claude-provider to use configurable MCP permissions
- Updated sdk-options factory functions for MCP support
- Added settings helpers for loading MCP configs

apps/ui/src/hooks/use-settings-migration.ts

@@ -21,6 +21,7 @@ import { useEffect, useState, useRef } from 'react';
 import { getHttpApiClient } from '@/lib/http-api-client';
 import { isElectron } from '@/lib/electron';
 import { getItem, removeItem } from '@/lib/storage';
+import { useAppStore } from '@/store/app-store';
 
 /**
  * State returned by useSettingsMigration hook
@@ -227,6 +228,9 @@ export async function syncSettingsToServer(): Promise<boolean> {
       enableSandboxMode: state.enableSandboxMode,
       keyboardShortcuts: state.keyboardShortcuts,
       aiProfiles: state.aiProfiles,
+      mcpServers: state.mcpServers,
+      mcpAutoApproveTools: state.mcpAutoApproveTools,
+      mcpUnrestrictedTools: state.mcpUnrestrictedTools,
       projects: state.projects,
       trashedProjects: state.trashedProjects,
       projectHistory: state.projectHistory,
@@ -316,3 +320,42 @@ export async function syncProjectSettingsToServer(
     return false;
   }
 }
+
+/**
+ * Load MCP servers from server settings file into the store
+ *
+ * Fetches the global settings from the server and updates the store's
+ * mcpServers state. Useful when settings were modified externally
+ * (e.g., by editing the settings.json file directly).
+ *
+ * Only functions in Electron mode. Returns false if not in Electron or on error.
+ *
+ * @returns Promise resolving to true if load succeeded, false otherwise
+ */
+export async function loadMCPServersFromServer(): Promise<boolean> {
+  if (!isElectron()) return false;
+
+  try {
+    const api = getHttpApiClient();
+    const result = await api.settings.getGlobal();
+
+    if (!result.success || !result.settings) {
+      console.error('[Settings Load] Failed to load settings:', result.error);
+      return false;
+    }
+
+    const mcpServers = result.settings.mcpServers || [];
+    const mcpAutoApproveTools = result.settings.mcpAutoApproveTools ?? true;
+    const mcpUnrestrictedTools = result.settings.mcpUnrestrictedTools ?? true;
+
+    // Clear existing and add all from server
+    // We need to update the store directly since we can't use hooks here
+    useAppStore.setState({ mcpServers, mcpAutoApproveTools, mcpUnrestrictedTools });
+
+    console.log(`[Settings Load] Loaded ${mcpServers.length} MCP servers from server`);
+    return true;
+  } catch (error) {
+    console.error('[Settings Load] Failed to load MCP servers:', error);
+    return false;
+  }
+}