fix(js-sdk): stop CommandHandle.disconnect() leaking the output subscription

[mishushakov]

Description

This PR fixes two related issues in the command handle's event handling.

1. JS CommandHandle.disconnect() leaked the output subscription

disconnect() was fire-and-forget — it only triggered the transport abort and relied entirely on HTTP/2 abort propagation to stop events, which is unreliable under keepalive: onStdout/onStderr/onPty could keep firing for output produced after disconnect() returned.

disconnect() now sets a cooperative disconnected flag and aborts the transport. The flag is checked before every callback dispatch in the event loop, so once disconnect() returns no callback fires for output that arrives (or was buffered) after the call — even if the underlying abort hasn't torn the stream down yet. It does not wait for the event handler to drain, so it returns promptly even for an idle command (e.g. sleep) whose stream produces no further output, never blocks on an in-flight callback, and does not deadlock when awaited from inside a callback.

The async Python SDK was already correct here (disconnect() cancels the event-handling task), and the sync Python SDK has no background subscription (events are consumed only while the caller iterates). The added Python tests confirm both.

2. Exit code was lost when a disconnected consumer stopped on a flushed end-event chunk

When the end event flushes trailing decoder bytes (an incomplete multibyte sequence → replacement character) and the consumer stops iterating on the first flushed chunk, the generator was aborted before the result was assigned, so wait() failed as if the process never produced a result. The end handler now records the result before yielding the flushed chunks, across the JS, async Python, and sync Python SDKs.

Usage

const handle = await sandbox.commands.run(daemon, { background: true, stdin: true, onStdout })
await sandbox.commands.sendStdin(handle.pid, 'turn1\n')
await handle.disconnect() // resolves promptly; onStdout will not fire again
await sandbox.commands.sendStdin(handle.pid, 'turn2\n') // turn2 output never reaches onStdout

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Latest commit: a8b072c

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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[cursor]

PR Summary

Low Risk
Scoped to command stream subscription and disconnect semantics in the JS and Python SDKs, with no auth or data-path changes.

Overview
The JS CommandHandle.disconnect() could return while onStdout/onStderr/onPty still ran for output that arrived after the call, when the transport abort did not stop the stream immediately.

disconnect() now sets a disconnected flag and aborts via handleDisconnect() without waiting on the event loop, and the event handler skips callbacks once that flag is set. On stream end, the exit result is stored before any flushed decoder chunks are yielded so wait() still gets an exit code when iteration stops early after disconnect.

Python async and sync command handles get the same end-event ordering fix. Regression tests cover late output after disconnect, prompt disconnect on idle streams, and result recording after disconnect.

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Package Artifacts

Built from b4fc3bb. Download artifacts from this workflow run.

JS SDK (e2b@2.30.6-mishushakov-verify-bug-repro.0):

npm install ./e2b-2.30.6-mishushakov-verify-bug-repro.0.tgz

CLI (@e2b/cli@2.12.3-mishushakov-verify-bug-repro.0):

npm install ./e2b-cli-2.12.3-mishushakov-verify-bug-repro.0.tgz

Python SDK (e2b==2.29.5+mishushakov-verify-bug-repro):

pip install ./e2b-2.29.5+mishushakov.verify.bug.repro-py3-none-any.whl

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