fix(engine): diffFilePriority's vendored-directory pattern misses vendored/third_party/third-party/bower_components/jspm_packages

[claytonlin1110]

Summary

• diffFilePriority's priority-4 ("least-useful-to-review, never real collision evidence") directory alternation only matched vendor (singular), while the sibling isVendoredFileFrom matcher in packages/loopover-engine/src/signals/path-matchers.ts already recognizes vendor, vendored, third_party, third-party, bower_components, and jspm_packages.
• path-matchers.ts had this full set from its original creation (feat(signals): add slop path matchers and non-substantive-padding signal (#561) #752/feat(signals): classify build and CI configuration files in path-matchers (#561) #1045) and later additions (fix(signals): classify bower_components and jspm_packages as vendored #2777 added bower_components/jspm_packages) with no corresponding update to diff-file-priority.ts — the two matchers silently drifted apart.
• Practical effect: a file shared between two unrelated PRs under e.g. third_party/foo.js, vendored/bar.js, or bower_components/baz.js was ranked priority 0 ("ordinary source") instead of 4, so sharesMeaningfulFile (both call sites: packages/loopover-engine/src/signals/engine.ts and packages/loopover-engine/src/signals/predicted-gate-engine.ts) treated it as real collision evidence — inflating the collision/duplicate-cluster signal on exactly the kind of vendored-artifact path both call sites' own doc comments say should be excluded.
• Extended diffFilePriority's directory alternation to the full isVendoredFileFrom set, with a code comment cross-referencing path-matchers.ts as the source of truth to keep in sync. No other branches of diffFilePriority (lockfile/doc/test) were touched, per the issue's stated scope.
• Scope note: src/review/review-diff.ts and src/review/review-grounding.ts carry their own host-side copies of diffFilePriority with the identical gap, but are out of scope for this issue (not referenced in its Requirements/Links) and scripts/check-engine-parity.ts's twin-pair drift check only verifies marker presence (not byte-identical bodies) for this pair, so this scoped fix doesn't trip it.

Tests

• packages/loopover-engine/test/diff-file-priority.test.ts: added a case asserting priority 4 for a path under each newly-added directory name (vendored/x.js, third_party/x.js, third-party/x.js, bower_components/x.js, jspm_packages/x.js), plus a sharesMeaningfulFile regression test confirming a file shared only under third_party//bower_components/ no longer counts as meaningful collision evidence.

Validation

• npm run test --workspace @loopover/engine — 594/594 passing
• npm run build --workspace @loopover/engine && npm run typecheck — clean
• npm run engine-parity:drift-check — ok, 5 hand-duplicated file pairs agree
• npm run test:engine-parity && npm run test:live-gate-parity && npm run test:driver-parity — all passing
• npm run db:migrations:check && npm run db:schema-drift:check && npm run selfhost:env-reference:check && npm run miner:env-reference:check && npm run selfhost:validate-observability && npm run command-reference:check && npm run docs:drift-check && npm run manifest:drift-check — all clean
• npm run cf-typegen:check — no drift
• npm run actionlint — clean
• git diff --check — clean
• No UI-visible change, so no screenshots.

Closes #7526

[superagent-security]

Superagent didn't find any vulnerabilities or security issues in this PR.

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Tip

✅ LoopOver review result - approve/merge recommended

_{Review updated: 2026-07-20 21:37:51 UTC}

2 files · 1 AI reviewer · no blockers · readiness 98/100 · CI green · clean

✅ Suggested Action - Approve/Merge

• safe to merge

Review summary
This is a narrow, well-targeted regex fix aligning diffFilePriority's vendored-directory alternation with path-matchers.ts's isVendoredFileFrom set (adding vendored, third_party, third-party, bower_components, jspm_packages). The fix is correct and minimal — only the vendored-directory branch is touched, other branches untouched per stated scope. Tests directly exercise the new regex alternatives and the sharesMeaningfulFile downstream effect, which is the real collision-detection consequence described in the PR.

Nits — 4 non-blocking

• The PR's own scope note admits src/review/review-diff.ts and src/review/review-grounding.ts carry identical copies of diffFilePriority with the same gap but are left unfixed — worth confirming a follow-up issue exists rather than letting the drift persist silently.
• validate, validate-tests (4), and validate-tests (2) are listed as FAILED in CI STATUS; worth checking whether these are pre-existing/unrelated failures or caused by this change.
• Consider filing or linking a follow-up issue to update the two host-side copies (review-diff.ts, review-grounding.ts) so the three-way drift doesn't recur.
• Since scripts/check-engine-parity.ts only checks marker presence and not byte-identical bodies for this pair, consider strengthening that check to catch future silent drift like this one.

Decision drivers

• ✅ Code review — No blockers (1 reviewer)
• ✅ Gate result — Passing (No configured blocker found.)

Context & advisory signals — never blocks the verdict

Signal	Result	Evidence
Linked issue	✅ Linked	#7526
Related work	✅ No active overlap found	No same-issue or scoped active PR overlap found.
Change scope	✅ 20/20	Low review scope from cached public metadata (1 linked issue).
Validation posture	✅ 25/25	PR body includes validation/test evidence.
Contributor workload	✅ 10/10	Author activity: 376 registered-repo PR(s), 247 merged, 85 issue(s).
Contributor context	✅ Confirmed Gittensor contributor	claytonlin1110; Gittensor profile; 376 PR(s), 85 issue(s).
Improvement	✅ Minor	risk: clean · value: minor

Review context

• Author: claytonlin1110
• Role context: outside_contributor
• Public audience mode: oss maintainer
• Lane context: Repository is configured for direct PR review.
• Public profile languages: not available
• Official Gittensor activity: 376 PR(s), 85 issue(s).
• PR-specific overlap: none found.

Contributor next steps

• Keep the PR focused and include validation evidence before maintainer review.

Signal definitions

• Related work = same linked issue, overlapping active PRs, or title/path similarity.
• Change scope = cached public metadata such as size labels, draft state, and review-burden hints.
• Validation posture = whether the PR provides enough public validation/test evidence for maintainer review.
• Contributor workload = public contributor activity and cleanup pressure, not a repo-wide quality failure.
• Contributor context = public GitHub/Gittensor identity context; non-Gittensor status is not a blocker.

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_{🟩 Safe / merged · 🟦 Advisory · 🟨 Held for review · 🟥 Blocked / closed}

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LoopOver approves — the gate is satisfied and CI is green.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.47%. Comparing base (37e7f86) to head (83e0c91).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7540      +/-   ##
==========================================
- Coverage   88.47%   88.47%   -0.01%     
==========================================
  Files         720      720              
  Lines       75733    75733              
  Branches    22547    22548       +1     
==========================================
- Hits        67008    67004       -4     
  Misses       7679     7679              
- Partials     1046     1050       +4     

Flag	Coverage Δ
shard-1	32.99% <0.00%> (-0.05%)	⬇️
shard-2	36.85% <0.00%> (ø)
shard-3	25.66% <0.00%> (ø)
shard-4	38.88% <0.00%> (ø)
shard-5	34.21% <100.00%> (ø)
shard-6	36.22% <0.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...s/loopover-engine/src/review/diff-file-priority.ts	100.00% <100.00%> (ø)

... and 1 file with indirect coverage changes