Fix Swift compiler errors in AI Assistant view controllers

[codegen-sh]

This PR fixes several Swift compiler errors in the AI Assistant view controllers:

Fixed in AIViewController.swift:

1. Added missing frame parameter in UITableView initialization
2. Added override keyword for refreshContent() method
3. Fixed missing contextual base for .systemGroupedBackground and .singleLine by adding explicit types
4. Removed unnecessary try expression in fetchRecentChatSessions call

Fixed in ChatViewController.swift:

1. Fixed several "expected ')' in expression list" errors by replacing DispatchQueue.main.async(execute: { ... }) with DispatchQueue.main.async { ... }
2. Fixed trailing comma in NSLayoutConstraint array

These changes should resolve all the compiler errors mentioned in the issue.

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