/**
 * [WHO]: diagnosticsExtension - diagnostic:event listener, /report-issue command, silent auto-upload on agent_end
 * [FROM]: Depends on core/extensions-host/types, @catui/tui, ./diagnostic-buffer, ./reporter, ./types
 * [TO]: Auto-loaded by builtin-extensions.ts as a default extension before diagnostic producers
 * [HERE]: extensions/builtin/diagnostics/index.ts - extension-owned diagnostic buffer; background failures auto-upload silently at agent_end plus delayed sweep, /report-issue stays for explicit user-initiated bundles
 */
import type { ExtensionAPI } from "../../../core/extensions-host/types.js";
export default function diagnosticsExtension(api: ExtensionAPI): Promise<void>;