Support Xcode and iOS 27

This release adds support for Xcode 27 and iOS 27.

Breaking Changes

• Made the color parameter of CastButton apply only to the devices view. The button icon now follows standard SwiftUI styling. If your app passed a custom color to style the icon, apply tint(_:) or foregroundStyle(_:) to the button instead.
• Moved the @MainActor annotation from the CastDelegate and Castable protocols to their methods, so that types that aren't main actor-isolated can conform to them. Conforming types no longer inherit main actor isolation from these protocols. If your type relied on it, annotate the type with @MainActor explicitly.

Improvements

• Made the properties of CastConfiguration and CastAssetURLConfiguration mutable, so that you can create a default configuration and adjust only the settings you need.
• Improved the legibility of the CastButton devices popover on dark backgrounds (iOS 16.4+).

Fixes

• Fixed CastPlayer.playbackSpeed briefly reporting zero during seeks.

Toolchain Updates

• Raised the Swift tools version to 6.4. Xcode 27 is now required.

What's Changed

• Loosen main actor requirements by @defagos in #294
• Enable standard APIs for Cast button styling by @defagos in #297
• Bump fastlane from 2.237.0 to 2.238.0 in the gems group by @dependabot[bot] in #299
• Allow configuration via default creation and selected mutation by @defagos in #298
• Pin stale action to commit SHA by @defagos in #301
• Bump mikepenz/action-junit-report from 6.4.2 to 6.5.0 in the actions group by @dependabot[bot] in #302
• Bump fastlane from 2.238.0 to 2.239.0 in the gems group by @dependabot[bot] in #303
• Bump fastlane from 2.239.0 to 2.240.0 in the gems group by @dependabot[bot] in #304
• Bump fastlane from 2.240.0 to 2.240.1 in the gems group by @dependabot[bot] in #305
• Bump github.com/srgssr/google-cast-sdk from 4.8.4 to 4.8.6 in the packages group by @dependabot[bot] in #306
• Update for Xcode and iOS 27 by @defagos in #300
• Restore item selection in lists by @waliid in #308
• Support chapters in the demo app by @waliid in #310
• Improve devices popover legibility on dark backgrounds by @defagos in #309
• Avoid temporarily setting speed to zero during seeks by @defagos in #311
• Bump mikepenz/action-junit-report from 6.5.0 to 6.6.0 in the actions group by @dependabot[bot] in #313
• Bump mikepenz/action-junit-report from 6.6.0 to 6.6.1 in the actions group by @dependabot[bot] in #316
• Parse chapters using the Pillarbox standard data format by @defagos in #317
• Bump fastlane from 2.240.1 to 2.241.0 in the gems group by @dependabot[bot] in #318
• Bump fastlane from 2.241.0 to 2.241.1 in the gems group by @dependabot[bot] in #319
• Enable trailing comma SwiftLint rule by @defagos in #320
• Polish documentation by @defagos in #322
• Bump fastlane from 2.241.1 to 2.241.2 in the gems group by @dependabot[bot] in #323
• Ensure configuration consistency by @defagos in #325
• Update dependencies by @defagos in #324

Full Changelog: 3.0.1...4.0.0