ref(span-buffer): Remove flusher and buffer logger options

[untitaker]

Summary

• Remove spans.buffer.flusher-cumulative-logger-enabled option and FlusherLogger class
• Remove spans.buffer.flusher.log-flushed-segments option and associated logging
• Remove spans.buffer.evalsha-cumulative-logger-enabled option and BufferLogger class

These logging options were used for debugging during development but are no longer needed.

Refs STREAM-881

[linear-code]

STREAM-881

[fpacifici]

IF you remove the logger you also have to remove the script to parse them

• https://github.com/getsentry/sentry/tree/master/src/sentry/spans/log_analyzer
• docs https://github.com/getsentry/sentry/tree/master/src/sentry/spans#gcp-log-analyzer-tool

But, as I said below, I would not remove the buffer logger till we do not get rid of OTLP enrichment. We still have possible failure modes where specific traces can become problematic. Having the log and the log analyzer allow us to quickly identify the trace.

[fpacifici]

I would not remove the buffer logger till we do not get rid of OTLP enrichment altogether.
There are still possible failure modes where we would want to identify a problematic trace.

Ok to remove the flusher one

[untitaker]

removed the flusher logger only.

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit d9ae398. Configure here.}

[untitaker]

have to revert this to investigate another instance of a single redis shard running hot

[getsentry-bot]

revert failed (conflict? already reverted?) -- check the logs

[github-actions]

Backend Test Failures

Failures on 2592342 in this run:

tests/snuba/api/endpoints/test_project_trace_item_details.py::ProjectTraceItemDetailsEndpointTest::test_details_exposes_arrays — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/snuba/api/endpoints/test_project_trace_item_details.py:231: in test_details_exposes_arrays
    assert by_name["stack.filename"]["type"] == "array"
           ^^^^^^^^^^^^^^^^^^^^^^^^^
E   KeyError: 'stack.filename'