fix: resolve admin "Keep selected" duplicates when transaction thread…

[yusufdeveloper2903]

Explanation of Change

When an admin resolves duplicate expenses submitted by another member via "Resolve duplicates" → "Keep selected" → "Confirm", the duplicates were not resolved — the DUPLICATED_TRANSACTION violation reappeared after the next pull.

Root cause: in resolveDuplicates, a duplicate was dropped from the RESOLVE_DUPLICATES payload whenever its transaction thread (childReportID) was missing. Transaction threads are created lazily, so when an admin resolves from the workspace chat without opening each expense, transactionThreadReportIDMap is empty and every duplicate hit the skip → the backend received an empty transactionIDList and held nothing.

Fix (in src/libs/actions/IOU/Duplicate.ts):

1. The held duplicate's transactionID + hold reportActionID and the comment.hold optimistic update are now added to the payload before the thread check. Only the thread-keyed optimistic hold report action is guarded behind a defined transactionThreadReportID (so we never write to report_actions_undefined).
2. The kept transaction's dismissed-violation action is guarded the same way — when its thread is missing it is skipped, while dismissedViolationReportActionID is still sent so the backend records the dismissal.
3. A duplicate with no IOU action at all is still skipped, and the previous comment.hold value is restored on failure.

Unit tests were added for both missing-thread paths (held duplicate and kept transaction) plus the preserved skip when the IOU action is absent.

Fixed Issues

$ #92845
PROPOSAL: #92845 (comment)

Tests

1. Log in as an admin, create a Collect workspace, and invite a member.
2. As the member, submit two identical expenses (same amount, merchant, date, currency) to the workspace chat so they are flagged as duplicates.
3. As the admin, open the workspace chat without opening the individual expenses.
4. Select a duplicated expense → Resolve duplicates → Keep selected → follow the flow → Confirm.
5. Verify the "Duplicated transaction" violation is removed, the kept expense stays, and the other duplicate is put on hold.
6. Reload the app and verify the violation does not reappear.

• Verify that no errors appear in the JS console

Offline tests

1. Follow steps 1–3 above, then go offline.
2. Complete the "Keep selected" → "Confirm" flow while offline.
3. Verify the violation is removed and the duplicate is held optimistically.
4. Go back online and verify the state is preserved; if the request fails, verify the violations and holds are rolled back.

QA Steps

Same as tests.

• Verify that no errors appear in the JS console

PR Author Checklist

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Screenshots/Videos

Android: Native

Android: mWeb Chrome

iOS: Native

After fix:

REC-20260721134626.mp4

iOS: mWeb Safari

MacOS: Chrome / Safari

After fix:

REC-20260721135136.mp4

[melvin-bot]

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