fix: update docs and barrel imports for task_system default

src/plugin-handlers/tool-config-handler.ts

@@ -1,6 +1,6 @@
 import type { OhMyOpenCodeConfig } from "../config";
 import { getAgentDisplayName, getAgentListDisplayName } from "../shared/agent-display-names";
-import { isTaskSystemEnabled } from "../shared/task-system-enabled";
+import { isTaskSystemEnabled } from "../shared";
 
 type AgentWithPermission = { permission?: Record<string, unknown> };