* perf: optimize large session reconnect by adding file-size threshold to tail optimization (#6241)
When a sidecar JSON file exceeds 500 KB, the display-path tail optimization
now fires even if the message count is within the raw_budget. This prevents
sessions with few messages but large tool outputs (multi-MB JSON) from
forcing a full-scan merge of all messages on reconnect.
Changes:
- Added _sidecar_file_exceeds_threshold() helper
- Added _SIDECAR_BYTE_TAIL_THRESHOLD = 500_000 constant
- Fall-through to truncation in _state_db_since_timestamp_for_limited_display
when the sidecar file exceeds the threshold, regardless of message count
* CHANGELOG: byte-size reconnect tail optimization (#6260)
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Co-authored-by: webtecnica <webtecnica@users.noreply.github.com>
Co-authored-by: nesquena-hermes <agent@nesquena-hermes>
