ref(spans): remove chunk-oversized-segments option

[lvthanh03]

Removing the chunking option from being used in the business logic so that the default behaviour is chunking up a segment before flushing.

[cursor]

Cursor Bugbot has reviewed your changes and found 2 potential issues.

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[github-actions]

Backend Test Failures

Failures on 9a50752 in this run:

tests/sentry/spans/test_buffer.py::test_dropped_spans_emit_outcomes[cluster-nochunk] — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/spans/test_buffer.py:1052: in test_dropped_spans_emit_outcomes
    assert mock_track_outcome.called, "track_outcome should be called when spans are dropped"
E   AssertionError: track_outcome should be called when spans are dropped
E   assert False
E    +  where False = <MagicMock name='track_outcome' id='140405987349168'>.called

tests/sentry/spans/test_buffer.py::test_dropped_spans_emit_outcomes[cluster-chunk1] — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/spans/test_buffer.py:1052: in test_dropped_spans_emit_outcomes
    assert mock_track_outcome.called, "track_outcome should be called when spans are dropped"
E   AssertionError: track_outcome should be called when spans are dropped
E   assert False
E    +  where False = <MagicMock name='track_outcome' id='140405881445344'>.called

tests/sentry/spans/test_buffer.py::test_dropped_spans_emit_outcomes[single-nochunk] — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/spans/test_buffer.py:1052: in test_dropped_spans_emit_outcomes
    assert mock_track_outcome.called, "track_outcome should be called when spans are dropped"
E   AssertionError: track_outcome should be called when spans are dropped
E   assert False
E    +  where False = <MagicMock name='track_outcome' id='140405858490688'>.called

tests/sentry/spans/test_buffer.py::test_dropped_spans_emit_outcomes[single-chunk1] — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/sentry/spans/test_buffer.py:1052: in test_dropped_spans_emit_outcomes
    assert mock_track_outcome.called, "track_outcome should be called when spans are dropped"
E   AssertionError: track_outcome should be called when spans are dropped
E   assert False
E    +  where False = <MagicMock name='track_outcome' id='140405858499760'>.called