fix(server): include Codex archived_sessions in usage scan

[bulbulogludemir]

Codex moves rolled-out sessions to archived_sessions, but the usage scanner only reads sessions/, so any archived history silently contributes zero cost to the Usage page.

This change:

• resolves archived_sessions alongside sessions for every Codex home (deduped per directory, so aliased/shadow homes still scan once),
• gives Codex usage events a stable dedupeKey (session, timestamp, model, token totals) so a rollout present in both directories is charged exactly once; genuinely different sessions/events keep distinct keys,
• bumps USAGE_SCAN_CACHE_VERSION 3 → 4 because v3 Codex records carry null keys and would double-count archived copies.

Tests:

• usageTranscripts.test.ts: identical events parsed from two copies share one dedupeKey.
• UsageService.test.ts: an identical archived rollout copy is scanned (sources 4 → 5, files 4 → 5) with totals unchanged.
• usageScanCache.test.ts: previous-version rejection now targets v3.
• apps/server typecheck passes; usage test files pass (usageTranscripts/usageScanCache/usageAggregation green, modified UsageService account test green — 2 pre-existing it.live timeouts in that file also fail on clean main in this environment).

Summary by CodeRabbit

• Bug Fixes
  • Usage reporting now includes archived Codex sessions, improving completeness when sessions are moved or copied.
  • Archived and active copies of the same session are counted only once, preventing duplicate usage charges.
  • Usage scan data is refreshed safely to account for updated duplicate-detection behavior.
• Tests
  • Added coverage confirming consistent identification of copied Codex rollout records and correct usage totals.

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[macroscopeapp]

Approvability

Verdict: Not approved

Macroscope's review found this PR not approvable — The PR changes production usage metering by adding archived Codex sessions to priced summaries and changing cross-file duplicate charging behavior. It is narrowly scoped and tested, but metering changes require human review.

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ℹ️ Recent review info

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Run ID: 5b4e44c6-fa7a-4896-892b-99dbb8e2d108

📥 Commits

Reviewing files that changed from the base of the PR and between bf3be75 and 846d0d0.

📒 Files selected for processing (6)

• apps/server/src/usage/UsageService.test.ts
• apps/server/src/usage/UsageService.ts
• apps/server/src/usage/usageScanCache.test.ts
• apps/server/src/usage/usageScanCache.ts
• apps/server/src/usage/usageTranscripts.test.ts
• apps/server/src/usage/usageTranscripts.ts

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📝 Walkthrough

Walkthrough

Codex usage scanning now includes archived_sessions. Codex records with session IDs receive stable dedupe keys. The scan-cache format version increases, and tests cover duplicate rollout files and stale cache entries.

Changes

Codex usage deduplication

Layer / File(s)	Summary
Stable Codex record identity apps/server/src/usage/usageTranscripts.ts, apps/server/src/usage/usageTranscripts.test.ts	parseCodexLine generates a composite dedupeKey for records with session IDs. Tests verify identical events produce equal non-null keys.
Archived session scanning apps/server/src/usage/UsageService.ts, apps/server/src/usage/UsageService.test.ts	resolveTranscriptDirs scans Codex archived_sessions. Tests verify both rollout copies are scanned while output tokens remain charged once.
Scan-cache version invalidation apps/server/src/usage/usageScanCache.ts, apps/server/src/usage/usageScanCache.test.ts	The cache format version increases from 3 to 4. Tests reject documents using the previous version.

Priority: ⬇️ Low

Estimated code review effort: 3 (Moderate) | ~20 minutes

Change: Bug fix

Suggested reviewers: t3dotgg

Merge Risk: ⚪ Minimal · up to 846d0

The archived-session scan, deduplication, and cache invalidation changes have no identified merge-blocking risk.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the primary change: including Codex archived_sessions in the server usage scan.
Description check	✅ Passed	The description clearly explains what changed, why it changed, the deduplication approach, cache-version impact, and test coverage. It does not use the template headings or include the checklist, but …
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 1 functions across 6 files.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[bulbulogludemir]

Ready for human review (per the Macroscope approability note — this touches usage metering, so auto-approval is off by policy).

Verification summary:

• New behavior covered by tests: identical Codex rollout copies across sessions/ and archived_sessions/ are scanned but charged once; archive-only sessions now contribute usage; moving a rollout into archives keeps totals stable.
• apps/server typecheck passes; new/updated tests in usageTranscripts, usageScanCache and the modified UsageService account test pass. (2 pre-existing it.live timeouts in UsageService.test.ts also fail on clean main in this environment, unrelated to this change.)
• Also validated the parser/aggregator against ~2.5k real Codex transcript files (sessions + archives): 0 read errors.