fix: drain stdout before resolving when a child holds the pipe past exit (#5753)

packages/coding-agent/src/core/tools/bash.ts

@@ -289,6 +289,7 @@ export function createBashToolDefinition(
 			const resolvedCommand = commandPrefix ? `${commandPrefix}\n${command}` : command;
 			const spawnContext = resolveSpawnContext(resolvedCommand, cwd, spawnHook);
 			const output = new OutputAccumulator({ tempFilePrefix: "pi-bash" });
+			let acceptingOutput = true;
 			let updateTimer: NodeJS.Timeout | undefined;
 			let updateDirty = false;
 			let lastUpdateAt = 0;
@@ -334,11 +335,13 @@ export function createBashToolDefinition(
 			}
 
 			const handleData = (data: Buffer) => {
+				if (!acceptingOutput) return;
 				output.append(data);
 				scheduleOutputUpdate();
 			};
 
 			const finishOutput = async () => {
+				acceptingOutput = false;
 				output.finish();
 				clearUpdateTimer();
 				emitOutputUpdate();