Fix Swift compilation errors and warnings

[codegen-sh]

This PR fixes the Swift compilation errors and warnings reported by XCPretty:

1. Fixed missing closing brace at the end of the UITableView DataSource & Delegate extension in LibraryViewController.swift (line 339)
2. Added @preconcurrency annotation to the WebKit import in WebViewController.swift to suppress Sendable-related warnings

These changes should resolve the following issues:

• expected '}' at end of extension error
• expected declaration error
• add '@preconcurrency' to suppress 'Sendable'-related warnings from module 'WebKit' warning

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