fix: suppress buffer error for mls decrypt transaction [WPB-16233]

[Garzas]

WPB-16233 [Android] Catch and suppress buffer errors inside transaction

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PR Submission Checklist for internal contributors

• The PR Title

  • conforms to the style of semantic commits messages¹ supported in Wire's Github Workflow²
  • contains a reference JIRA issue number like SQPIT-764
  • answers the question: If merged, this PR will: ... ³

• The PR Description

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What's new in this PR?

Issues

• When receiving out-of-order commits (e.g., when a client is missing a preceding commit), the MLS client was throwing a BufferedFutureMessage exception instead of buffering and persisting the message.
• This led to transactions always rolling back and no buffered messages actually being saved.

Causes

• The code did not properly detect or handle MlsException.BufferedFutureMessage (wrapped in CoreCryptoException.Mls) within the transactional decryption flow.
• As a result, any out-of-order commit triggered a rollback, preventing buffering logic from persisting the messages that should be processed later.

Solutions

• Updated the decryptMessage flow to wrap calls in a transactional API and specifically catch BufferedFutureMessage exceptions, allowing the transaction to commit and the message to be buffered rather than rolled back.
• Added tests verifying that out-of-order commits no longer throw exceptions and that previously buffered commits are eventually flushed once the missing epoch is processed.

[github-actions]

Test Results

3 367 tests   3 257 ✅  5m 32s ⏱️
  572 suites    110 💤
  572 files        0 ❌

Results for commit a955880.

♻️ This comment has been updated with latest results.

[datadog-wireapp]

Datadog Report

Branch report: fix/suppress-mls-buffer-error
Commit report: 4546218
Test service: kalium-jvm

✅ 0 Failed, 3257 Passed, 110 Skipped, 1m 3.27s Total Time

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[MohamadJaara]

LGTM

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

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Additional details and impacted files

@@                 Coverage Diff                  @@
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  Coverage                     ?   54.54%           
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  Files                        ?     1252           
  Lines                        ?    36684           
  Branches                     ?     3740           
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  Hits                         ?    20008           
  Misses                       ?    15253           
  Partials                     ?     1423           

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