Add AppStorage initializer for Date? (optional Date)

[leogdion]

Description

RadiantKit's AppStorage extensions are missing an initializer for optional Date (Date?) types. This prevents using @AppStorage(for:) with AppStored types that have Value = Date?.

Current Behavior

When attempting to use:

public enum Onboarding {
  public enum Glass: RadiantKit.AppStored {
    public static let keyType: RadiantKit.KeyType = .reflecting
    public typealias Value = Date?
  }
}

// Usage:
@AppStorage(for: Onboarding.Glass.self) private var onboardedAt

This results in a compilation error:

error: no exact matches in call to initializer

Expected Behavior

An initializer should exist in AppStorage+ExpressibleByNilLiteral.swift to support Date?:

extension AppStorage where Value: ExpressibleByNilLiteral {
  public init<AppStoredType: AppStored>(
    for type: AppStoredType.Type,
    store: UserDefaults? = nil
  )
  where
    AppStoredType.Value == Value,
    Value == Date? {
    self.init(type.key, store: store)
  }
}

Additional Context

The extension file already includes initializers for:

• Bool?
• Int?
• Double?
• String?
• URL?
• Data?
• Optional RawRepresentable types

But is missing Date?, which is a common type for tracking timestamps in UserDefaults.

Location

File: Sources/RadiantKit/PropertyWrappers/AppStorage/AppStorage+ExpressibleByNilLiteral.swift