fix: ignore subconversation message fail system message [WPB-15684]

[Garzas]

WPB-15684 [Android] SubConversation messages sends system messages when fails to decrypt

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• 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

Previously, system messages were being sent for MLS messages even when the subConversationId was present. This behavior was incorrect because sub-conversations should not trigger system messages for decryption errors.

Solutions

1. Sub-Conversation Check:

   • Updated the code to skip sending system messages if subConversationId is not null when handling InformUser failures.
   • This ensures that sub-conversation-specific events are handled correctly without unnecessary system messages.

2. Comprehensive Testing:

   • Added a new test case to verify that handleDecryptionError is not invoked when subConversationId is present.
   • Ensured that all related scenarios are covered to prevent regressions.

[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

[github-actions]

Test Results

3 348 tests  +1   3 240 ✅ +1   5m 22s ⏱️ - 1m 2s
  572 suites ±0     108 💤 ±0 
  572 files   ±0       0 ❌ ±0 

Results for commit 0e89498. ± Comparison against base commit 55e6c38.

♻️ This comment has been updated with latest results.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 10 lines in your changes missing coverage. Please review.

Project coverage is 54.52%. Comparing base (55e6c38) to head (0e89498).

Files with missing lines	Patch %	Lines
...ver/conversation/message/NewMessageEventHandler.kt	0.00%	9 Missing and 1 partial ⚠️

Additional details and impacted files

@@                Coverage Diff                 @@
##           release/candidate    #3245   +/-   ##
==================================================
  Coverage              54.51%   54.52%           
==================================================
  Files                   1250     1250           
  Lines                  36554    36555    +1     
  Branches                3698     3699    +1     
==================================================
+ Hits                   19929    19933    +4     
+ Misses                 15224    15222    -2     
+ Partials                1401     1400    -1     

Files with missing lines	Coverage Δ
...ver/conversation/message/NewMessageEventHandler.kt	84.61% <0.00%> (+1.12%)	⬆️

... and 4 files with indirect coverage changes

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[datadog-wireapp]

Datadog Report

Branch report: fix/ignore-subconversation-message-fail-system-message
Commit report: 3d71598
Test service: kalium-jvm

✅ 0 Failed, 3240 Passed, 108 Skipped, 59.81s Total Time