fix(session): commit manual charges before work

[brendanjryan]

Motivation

A manual stream charge must survive cancellation after billable work begins. Previously, disconnecting before emission released the pending charge.

Summary

• Commit manual charges before stream.charge() resolves, retaining them on cancellation and generator failure.
• Run the post-commit hook before allowing the generator to continue.
• Remove reservation renewal during generator work, since manual charges are already committed.

async function* generate(stream) {
  await stream.charge()
  yield await performBillableWork()
}

Key design considerations

• An awaited manual charge is durable even if subsequent work fails; callers should charge only for work they intend to bill.
• Automatic iterables retain per-emission billing. Use manual charging to account for work before delivery.
• Uncommitted reservations still expire and are released on cancellation.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-03T00:01:21.863688Z	8b0473b	PR opened

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commit: 8b0473b