kvserver: log traces from replicate queue on errors or slow processing

[cockroach-teamcity]

Exalate commented:

Related PR: https://github.com/cockroachdb/cockroach/pull/86007 Commit: https://github.com/cockroachdb/cockroach/commit/6c45224e0af91b1d4940f93e52f2bce4dba18414

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Release note (ops change): Added logging on replicate queue processing in the presence of errors or when the duration exceeds 50% of the timeout.

Release justification: Low risk observability change.

Jira Issue: DOC-5777