fix(shutdown): Update known lifecycle flow to warn not error

[taylorchandleryoung]

Summary

We received feedback and confusion around Error writing acknowledgement, dropping connection. This is a lifecycle event, not an error, so we can likely downgrade to warn in this case.

Updating the flow to match the treatment of TcpSocketConnectionShutdown (warn + connection shutdown counter, no component_errors_total increment).

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• Bug fix
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• Performance

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[github-actions]

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[taylorchandleryoung]

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[graphcareful]

Another idea that came to mind, might this also be potentially misleading? There are other places the connection can be shutdown, I see StreamClosedError and DecoderFramingError, we would then have to increment this counter on those cases too otherwise the metric isn't 100% acccurate.

I think this counter can maybe be placed somewhere else where we would be exiting the connection - gracefully or ungracefully, since it doesn't really depend on those conditions to be incremented.