Fix #4837: Default 'Enable MCP Server Creation' to false

- Changed enableMcpServerCreation default value from true to false
- This reduces token usage and provides cleaner system prompts for most users
- Users can still manually enable the setting if needed

Author: roomote

webview-ui/src/context/ExtensionStateContext.tsx

@@ -163,7 +163,7 @@ export const ExtensionStateContextProvider: React.FC<{ children: React.ReactNode
 		terminalOutputLineLimit: 500,
 		terminalShellIntegrationTimeout: 4000,
 		mcpEnabled: true,
-		enableMcpServerCreation: true,
+		enableMcpServerCreation: false,
 		alwaysApproveResubmit: false,
 		requestDelaySeconds: 5,
 		currentApiConfigName: "default",