Fix Swift compilation errors in AI Assistant views

[codegen-sh]

This PR fixes several Swift compilation errors in the AI Assistant views:

1. In AIViewController.swift:

   • Added missing frame parameter to UITableView initialization
   • Fixed enum references by using fully qualified names (UIColor, UITableViewCell.SeparatorStyle)
   • Removed try keyword from fetchRecentChatSessions since it doesn't throw
   • Fixed the ViewControllerRefreshable conformance by using override instead of extension

2. In ChatViewController.swift:

   • Fixed DispatchQueue.main.async syntax by using trailing closure syntax consistently
   • Fixed parentheses matching in several places

These changes resolve all the compilation errors reported in the build log.

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