Nick Steele a6baf8867c Signal abandonment of unanswered MCP elicitations (#51611) ...

## Why

Published MCP elicitation requests could lose their response waiter without notifying the event consumer that the request was no longer answerable.

## What changed

- Add `ElicitationAbandoned` with the original server name and response token for requests published through unbounded event channels.
- Emit abandonment exactly once when a waiter is dropped, response delivery fails, or the MCP runtime shuts down.
- Close the elicitation router during shutdown, reject new requests on unbounded sources, and wait for terminal deliveries before shutdown completes. Preserve bounded sources' request-only behavior and backpressure.

## Testing

Add router tests for ordered, exactly-once abandonment, closed receivers, failed response delivery, shutdown coordination, and bounded-channel backpressure. Add a core integration scenario verifying that a pending form's abandonment precedes `ShutdownComplete`.

GitOrigin-RevId: 53fe9f4a8b32f7324be180288aa492f31f4d2057

2026-10-07 07:57:14 +00:00

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json

Add thread ID exclusions to thread/list (#51595)

2026-10-07 06:07:47 +00:00

precomputed

Signal abandonment of unanswered MCP elicitations (#51611)

2026-10-07 07:57:14 +00:00

typescript

Add thread ID exclusions to thread/list (#51595)

2026-10-07 06:07:47 +00:00