feat: large video previews - WPB-21076

[OlivellaO]

WPB-21076 [iOS] Large video previews in a conversation message

Issue

What was done in this PR:

1. Adding new View for large Video preview files.
2. Update WireCellsAttachmentsPreviewItemView to use the new large video preview.

Testing

Using a version that has Wire Cells enabled, send a single video file on a chat. When single video is shared, large video preview should be shown.

UI test can't be done, no way of mocking AsyncImage.

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Checklist

• [x] Title contains a reference JIRA issue number like [WPB-XXX].
• [x] 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.