feat: add meetings tab and developer flag - WPB-20271

[KaterinaWire]

WPB-20271 [iOS] Main navigation item including a displayable CTA

Issue

Add Meetings tab bar item and hide it behind the developer flag:

Design iPhone
Design iPad

Testing

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

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0 suites  0 💤
0 files    0 ❌

Results for commit c93292f.

♻️ This comment has been updated with latest results.

[netbe]

left one comment before approving, also looking at the ticket do we need to remove the archive conversation tab and move it to conversation filter?

[netbe]

question: didn't you mean ?

Suggested change

	await mainCoordinator.showSettings()
	await mainCoordinator.showMeetings()

[samwyndham]

Looks good. I'll hold off approving until @netbes comment is resolved