Addresses https://github.com/coder/internal/issues/1589. Supersedes
https://github.com/coder/coder/pull/26455. The previous fix did not
handle the case where there were 2 runners for the same chat: one
shutting down and one being bootstrapped. The one shutting down could
queue a stale state update which would cause the new runner to
immediately exit.
This PR adds logging when the chat runner retries and exits because of
an error. It also adds a 15-minute task timeout to ensure that stuck
tasks do not hang forever.
Hugo Dutka