[ADD] News, Browse and Settings views ported to SwiftUI

This commit contains WIP SwiftUI versions of most of the views in SideStore.

AltStore/View Extensions/Styles/PillButtonStyle.swift

@@ -0,0 +1,46 @@
+//
+//  PillButtonStyle.swift
+//  SideStore
+//
+//  Created by Fabian Thies on 18.11.22.
+//  Copyright © 2022 Fabian Thies. All rights reserved.
+//
+
+import SwiftUI
+
+struct PillButtonStyle: ButtonStyle {
+    
+    let tintColor: UIColor
+    var progress: Progress?
+    
+    func makeBody(configuration: Configuration) -> some View {
+        ZStack {
+            if progress == nil {
+                configuration.label
+                    .opacity(configuration.isPressed ? 0.4 : 1.0)
+            } else {
+                ProgressView()
+                    .progressViewStyle(DefaultProgressViewStyle())
+            }
+        }
+        .frame(minWidth: 40)
+        .padding(.horizontal, 16)
+        .padding(.vertical, 8)
+        .background(background)
+        .foregroundColor(self.progress == nil ? .white : Color(tintColor))
+        .clipShape(Capsule())
+    }
+    
+    var background: some View {
+        ZStack {
+            if let progress {
+                Color(tintColor).opacity(0.15)
+
+                ProgressView(progress)
+                    .progressViewStyle(PillButtonProgressViewStyle(tint: Color(tintColor)))
+            } else {
+                Color(tintColor)
+            }
+        }
+    }
+}