feat: Chat bubbles - Load real messages - WPB-19328

[dmitrysimkin]

WPB-19328 [iOS] Load real messages into new DataSource

Issue

• Created use case and repository to load conversation messages from DB
• LoadConversationMessagesRepository was implemented in main app because we can't for now use our core data models in SP packages
• Load real messages through new datasource
• Make WireMessagingAssembly be only one entry point to conversation screen functionality, fixed access modificators where needed

Testing

Turn on FF to use chat bubles and open conversation screen

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

1 951 tests   1 924 ✅  2m 13s ⏱️
  321 suites     27 💤
    2 files        0 ❌

Results for commit 14b08b7.

♻️ This comment has been updated with latest results.