fix: It shows Proteus then MLS conversation after enabling MLS for team - WPB-15027

[KaterinaWire]

WPB-15027 [iOS] Opening 1:1 shows proteus then mls conversation

Issue

"It shows briefly the former proteus conversation before it opens the MLS version, minus the proteus messages"
The messages from the Proteus conversation were not moved to the MLS conversation, and the other user still has a link to the previous Proteus conversation.

Solution

• log an error when resolving 1:1 conversations failed
• always try to migrate messages from the Proteus conversation to MLS and link the MLS conversation to other user if it's needed.
• add more comments.

Testing

steps are in the Jira ticket

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Checklist

• Title contains a reference JIRA issue number like [WPB-XXX].
• Description is filled and free of optional paragraphs.
• Adds/updates automated tests.

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UI accessibility checklist

If your PR includes UI changes, please utilize this checklist:

• Make sure you use the API for UI elements that support large fonts.
• All colors are taken from WireDesign.ColorTheme or constructed using WireDesign.BaseColorPalette.
• New UI elements have Accessibility strings for VoiceOver.

[github-actions]

Test Results

    7 files      8 suites   12m 5s ⏱️
6 932 tests 6 904 ✅ 28 💤 0 ❌
6 942 runs  6 914 ✅ 28 💤 0 ❌

Results for commit f7e650d.

♻️ This comment has been updated with latest results.

[datadog-wireapp]

Datadog Report

Branch report: fix/shows-proteus-then-mls-conversation
Commit report: 4fe6287
Test service: wire-ios-mono

✅ 0 Failed, 6632 Passed, 28 Skipped, 5m 32.06s Total Time

[netbe]

just left a small improvement