Mark DeleteGesture components unavailable on visionOS and tvOS

Added @available attributes to DGDeletableItem and the onDelete view modifier to explicitly mark them as unavailable on visionOS and tvOS platforms.

Author: Comic-Star-55

Sources/DeleteGesture/Public/DeletableItem.swift

@@ -10,6 +10,7 @@ import SwiftUI
 
 @available(iOS 18, macOS 15, *)
 @available(tvOS, unavailable)
+@available(visionOS, unavailable)
 public struct DGDeletableItem<Content: View>: View {
     ///Defines the action to execute when the Delete-Point entered
     private var onDelete: () -> Void

Sources/DeleteGesture/Public/View Modifier.swift

@@ -7,6 +7,8 @@
 import SwiftUI
 
 @available(macOS 15, iOS 18, *)
+@available(visionOS, unavailable)
+@available(tvOS, unavailable)
 extension View{
     public func onDelete(perform action: @escaping () -> Void) -> some View {
         DGDeletableItem(onDelete: action, content: { self })