Handle a race condition when a closing channel/connection fails to send 'channel.close_ok' on a terminated writer or socket

[Ayanda-D]

Proposed Changes

We see a race condition when a closing channel/connection fails to send 'channel.close_ok' to a client when the writer and/or socket is already closed or terminated.

2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0> ** Generic server <0.20291977.0> terminating
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0> ** Last message in was {'$gen_cast',ready_for_close}
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0> ** When Server state == {ch,
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0>                          {conf,closing,rabbit_framing_amqp_0_9_1,1,
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0>                           <0.20291963.0>,<0.20291984.0>,<0.20291963.0>,
...
...
...
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0>                                go,1,2,false,#{},#{},#{},undefined,
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0>                                undefined}}}},
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0>                          #Ref<0.1993375891.2291138563.124715>,true}
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0> ** Reason for termination ==
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0> ** {{shutdown,{writer,send_failed,closed}},
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0>     {gen_server,call,
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0>                 [<0.20291984.0>,
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0>                  {send_command_sync,{'channel.close_ok'}},
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0>                  infinity]}}
2026-06-04 17:20:27.578719-04:00 [error] <0.20291977.0>
2026-06-04 17:20:27.579447-04:00 [error] <0.20291977.0>   crasher:
2026-06-04 17:20:27.579447-04:00 [error] <0.20291977.0>     initial call: rabbit_channel:init/1
2026-06-04 17:20:27.579447-04:00 [error] <0.20291977.0>     pid: <0.20291977.0>
2026-06-04 17:20:27.579447-04:00 [error] <0.20291977.0>     registered_name: []
2026-06-04 17:20:27.579447-04:00 [error] <0.20291977.0>     exception exit: {{shutdown,{writer,send_failed,closed}},
2026-06-04 17:20:27.579447-04:00 [error] <0.20291977.0>                      {gen_server,call,
2026-06-04 17:20:27.579447-04:00 [error] <0.20291977.0>                                  [<0.20291984.0>,
2026-06-04 17:20:27.579447-04:00 [error] <0.20291977.0>                                   {send_command_sync,{'channel.close_ok'}},
2026-06-04 17:20:27.579447-04:00 [error] <0.20291977.0>                                   infinity]}}

Similar to #16598 we'd like to handle these channel terminations and crashes in a more graceful manner.

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