[j0sh]

Support sync and async on_payment_session callbacks in call_runner and expose LivePaymentSession.manifest_id for payment attribution. Invoke the callback for each new session.

Validate segCreds when parsing signer responses and remove redundant caller checks. Cover callback ordering, failures, and cancellation.

[eliteprox]

Still reviewing the error handling and payment status reporting, but here is one nit

[eliteprox]

Overall changes lgtm and test fine. Added one more suggestion to call_runner.

For context, we're using the on_payment_session callback with manifest_id in builder-core to confirm if payment was sent for the job.

[Copilot]

🟢 Approval recommended

Static review identified no blocking issues in callback handling or signer validation, and the added tests cover the key failure paths; tests were not executed.

No open issues 🎉

What changed in this PR

Adds payment-session notifications to runner calls, allowing callers to attribute payments using the session’s manifest ID.

Changes:

• Supports synchronous and asynchronous callbacks for each new payment session, before dispatching the paid request.
• Exposes LivePaymentSession.manifest_id and centralizes segCreds validation in signer-response parsing.
• Adds tests for callback ordering, failures, cancellation, and manifest attribution.

File	Description
tests/​test_live_runner.py	Tests callback sequencing, error propagation, and cancellation.
tests/​test_live_payment_session.py	Verifies the exposed manifest ID.
src/​livepeer_gateway/​remote_signer.py	Adds the manifest property and validates segment credentials centrally.
src/​livepeer_gateway/​live_runner.py	Implements payment-session callbacks and removes redundant validation.
src/​livepeer_gateway/​__init__.py	Exports the callback type.
CHANGELOG.md	Documents the new callback and manifest property.

_{Review effort: Balanced}

[Copilot]

🟢 Approval recommended

Static review found no blocking issues in callback handling, signer validation, or the accompanying tests; tests were not executed.

No open issues 🎉

_{Review effort: Balanced}