Reduce core coverage artifact size and retention

[itsjling]

The core-coverage upload included raw coverage data in tmp/; the audit found 108 artifacts using about 4.20 GiB, with the latest ZIP at 61.7 MB.

Upload only coverage/lcov-report/, coverage/lcov.info, and coverage/coverage-summary.json, and set retention-days: 7. Keep if: always() so failed checks still upload reports, and keep if-no-files-found: error.

Existing artifacts keep their original expiry dates. This change applies to future uploads and deletes no existing artifacts. Coverage thresholds, test selection, release artifacts, other workflows, and repository-wide retention remain unchanged.

Validation:

• corepack pnpm run setup and corepack pnpm run lint passed.
• corepack pnpm test passed, including coverage, browser, and platform checks. Coverage produced all three requested paths and met the existing thresholds.
• node --test tests/test-lanes.test.mjs passed all four tests; git diff --check passed.
• Fresh coverage output totalled 449,840,627 bytes, including 448,940,760 bytes in tmp/. The selected reports totalled 899,867 bytes across 16 files.
• A local ZIP of the selected paths, using DEFLATE level 6, measured 150,722 bytes (147.2 KiB). Checked ZIP integrity and verified every selected file against its source byte for byte, with no tmp/ entries. This is a local measurement; the GitHub artifact ZIP may differ slightly.
• corepack pnpm run check passed lint and build, then stopped with 367/368 tests passing: rebuilds a checkout review when a provider sees a worktree edit failed with ENOENT for a temporary diff-data.json. It passed in the coverage suite and on an isolated rerun. A second full check run on the same head, without the coverage suite running alongside it, repeated the same failure with 367/368 tests passing. The cause remains unconfirmed. Later check stages did not run. CI Product gate passed, but this local full-check failure remains unresolved.

CI artifact verification at ca3afc48ea6ea83a6e90817639a8624507cf69de:

• Test lanes run uploaded artifact 9971517270, sized 151,039 bytes, about 148 KiB. Downloaded the ZIP and verified its integrity and all 16 entries. It contains only the requested reports, totalling 899,421 bytes unpacked.
• GitHub reports creation at 2026-09-05T14:53:34Z and expiry at 2026-09-12T14:53:33Z, confirming seven-day retention. Existing artifacts keep their original expiry dates.
• Codex review found no major issues for this commit.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-05T14:57:55.947960Z	ca3afc4	Manual request

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[itsjling]

@codex review

Please review head ca3afc4 and report the result for that commit.

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. You're on a roll.

Reviewed commit: ca3afc48ea

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".