fix(cron): finalize compressed session tips (#67188)

[webtecnica]

Summary

• resolve a cron run's live compression tip before final title/completion
• use that resolved session consistently across success, exception, and inactivity-timeout finalization
• preserve the existing first-reason-wins completion contract and title de-duplication

Context

This adapts the still-valid preventive portion of Colin Greig's earlier carried cron fix (4ba5f6077b90e3b67814b8e50b31a8145178ba7c) to current upstream rather than cherry-picking the old patch.

The historical age/identifier-regex stale-session reconciler from that patch is intentionally not included: age and identifier shape do not prove that a long-running job is orphaned. The follow-up commit 71d8352ee4aaf6007c7ba8376496f0bbdef864a5 is also retired because it only repaired that omitted reconciler.

Previously the cron finalization block always used the original _cron_session_id captured before AIAgent started. When compression rotated the live agent onto a continuation session during the run, title/end_session targeted the stale original instead of the active continuation, losing the compressed session's data and violating the first-reason-wins contract.

Now the finally block queries SessionDB.get_compression_tip() to resolve the live tip and falls back to agent.session_id on lookup failure.

Changes

File	Lines	Change
cron/scheduler.py	+33 / -5	Resolve compression tip before title/end_session; use _final_cron_session_id in all paths
tests/cron/test_scheduler.py	+112 / -1	Added 4 tests: compression finalization, title dedup, lookup-failure fallback, timeout coverage
tests/test_hermes_state.py	+52 / -0	Added concurrent end_session audit test proving first-reason-wins contract

Validation

• 28 passed in tests/cron/test_scheduler.py (TestRunJobSessionPersistence)
• 1 passed in tests/test_hermes_state.py (concurrent end_session test)
• ruff check passed on all 3 modified files

Closes #67188

[alt-glitch]

This was generated by AI during triage.

Duplicate of #67188: the production cron finalization diff is byte-equivalent.

[teknium1]

Thanks for adapting the cron finalization fix to current main. The premise is verified: cron/scheduler.py:3634 and cron/scheduler.py:3659 finalize the original cron session, while legacy compression rotates agent.session_id and creates a continuation in agent/conversation_compression.py:868-902.

Problems

• This patch is byte-identical to still-open PR fix(cron): finalize compressed session tips #67188: gh pr diff 67221 --color=never | sha256sum and the equivalent fix(cron): finalize compressed session tips #67188 command both produced bd765740b88365097fb4a7f39c1a006205c800e13eda23a2b4b98db0e4df6089.

Suggested changes

• Keep one PR as the salvage source so the same cron finalization change is not reviewed or landed twice.

Automated hermes-sweeper review.

[teknium1]

Closing as a duplicate of #67188, which @colingreig opened ~100 minutes earlier — the two diffs are byte-identical (same sha256), so there is no salvageable delta here. #67188 is the vehicle moving forward.