line: support blocking and unblocking users

[highesttt]

No description provided.

[linear-code]

PLAT-39269

[indent]

Issues

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3 issues already resolved

• If getBlockedRecommendationIds fails, refreshBlockedContacts returns an error and discards the successful blocked-contact result. Blocks and unblocks made on the phone while offline are then missed, and unblocked users stay marked blocked. Treat the recommendation call as best-effort. (fixed by commit 8f8814e)
  _{Found by Indent Review Agent}
• HandleMatrixBlockUser doesn't update lc.blockedUsers after a successful block or unblock and relies on the op echo. Until the echo arrives, sends right after an unblock from Beeper still fail with "user is blocked on LINE". Update the cache and snapshot after SetContactBlocked succeeds. (fixed by commit 9b971b7)
  _{Found by Indent Review Agent}
• A block op whose Param2 isn't exactly "RECOMMEND" removes the MID from the recommendation fallback list. If the recommendation refresh later fails, the user is treated as newly unblocked and sends are allowed. Only add on RECOMMEND and leave the snapshot alone otherwise. (fixed by commit 9b971b7)
  _{Found by Indent Review Agent}

CI Checks

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Review agents

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Passed (1)

• Indent Review Agent · The latest change fixes the fallback-list issue and adds no regressions; nothing left to report.

Full results

Indent Review Agent

• Summary: The latest change fixes the fallback-list issue and adds no regressions; nothing left to report.
• Last ran on commit: 9b971b70
• Latest result

  {
    "summary": "The latest change fixes the fallback-list issue and adds no regressions; nothing left to report.",
    "findings": []
  }