feat(coding-agent): add startup profiling scripts for tui/rpc (#2497)

packages/coding-agent/src/main.ts

@@ -754,6 +754,11 @@ export async function main(args: string[]) {
 		stdinContent,
 	);
 	const isInteractive = !parsed.print && parsed.mode === undefined;
+	const startupBenchmark = isTruthyEnvFlag(process.env.PI_STARTUP_BENCHMARK);
+	if (startupBenchmark && !isInteractive) {
+		console.error(chalk.red("Error: PI_STARTUP_BENCHMARK only supports interactive mode"));
+		process.exit(1);
+	}
 	const mode = parsed.mode || "text";
 	initTheme(settingsManager.getTheme(), isInteractive);
 
@@ -848,8 +853,7 @@ export async function main(args: string[]) {
 			console.log(chalk.dim(`Model scope: ${modelList} ${chalk.gray("(Ctrl+P to cycle)")}`));
 		}
 
-		printTimings();
-		const mode = new InteractiveMode(session, {
+		const interactiveMode = new InteractiveMode(session, {
 			migratedProviders,
 			modelFallbackMessage,
 			initialMessage,
@@ -857,7 +861,21 @@ export async function main(args: string[]) {
 			initialMessages: parsed.messages,
 			verbose: parsed.verbose,
 		});
-		await mode.run();
+		if (startupBenchmark) {
+			await interactiveMode.init();
+			interactiveMode.stop();
+			stopThemeWatcher();
+			if (process.stdout.writableLength > 0) {
+				await new Promise<void>((resolve) => process.stdout.once("drain", resolve));
+			}
+			if (process.stderr.writableLength > 0) {
+				await new Promise<void>((resolve) => process.stderr.once("drain", resolve));
+			}
+			return;
+		}
+
+		printTimings();
+		await interactiveMode.run();
 	} else {
 		await runPrintMode(session, {
 			mode,