Updates for xcode beta (#123)

Author: noahsmartin

Sources/PreviewGallery/PreviewData.swift

@@ -23,7 +23,7 @@ public struct PreviewData {
     Set(previews.map { $0.module })
   }
 
-  public static var `default`: PreviewData {
+  @MainActor public static var `default`: PreviewData {
     self.init(previews: findPreviews())
   }
 }

Sources/PreviewGallery/PreviewGallery.swift

@@ -30,8 +30,9 @@ public struct PreviewGallery: View {
 
   let data: PreviewData
 
-  public init(data: PreviewData = .default) {
-    self.data = data
+  @MainActor
+  public init(data: PreviewData? = nil) {
+    self.data = data ?? .default
   }
 
   public var body: some View {

Sources/SnapshotPreviewsCore/SnapshotPreviewsCore.swift

@@ -94,6 +94,7 @@ public struct PreviewType: Hashable, Identifiable {
 
 #if compiler(>=5.9)
   @available(iOS 17.0, macOS 14.0, *)
+  @MainActor
   init?<A: PreviewRegistry>(typeName: String, registry: A.Type) {
     self.typeName = typeName
     self.fileID = A.fileID
@@ -142,6 +143,7 @@ public struct PreviewType: Hashable, Identifiable {
   public let platform: PreviewPlatform?
 }
 
+@MainActor
 public func findPreviews(
   shouldInclude: (String, String) -> Bool = { _, _ in true },
   willAccess: (String) -> Void = { _ in }) -> [PreviewType]