feat: add Meetings screen with tabs - WPB-20272

[KaterinaWire]

WPB-20272 [iOS] Meetings screen with tabs (Upcoming, Past)

Issue

This PR includes:

• Meetings screen with proper top bar including user avatar and title and two tabs to switch between different Meetings lists: Upcoming, Past (without cells for meeting details).
• Empty states

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.