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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🦋 Changeset detected

Latest commit: f686b3f

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

This PR includes changesets to release 2 packages

Name	Type
e2b	Patch
@e2b/python-sdk	Patch

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PR Summary

Medium Risk
Changes command stream lifecycle and when exit codes are visible; behavior is covered by new tests but affects long-running background commands.

Overview
In the JS SDK, CommandHandle.disconnect() could leave onStdout / onStderr / onPty firing after it returned when the transport abort did not stop the stream quickly. Disconnect now sets a flag that is checked before each callback dispatch so late output is not delivered, and it still returns without waiting on an idle or in-flight handler.

In the JS, async Python, and sync Python SDKs, handling the command end event used to yield flushed trailing decoder bytes before storing CommandResult. If iteration stopped on the first flushed chunk (including after disconnect), wait() could fail even though the process had exited. The result is now recorded before those trailing chunks are yielded.

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Package Artifacts

Built from 3685c65. 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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[matthewlouisbrockman]

should update changeset for the python before merging