Improve action handler spamming, fix nits & add comments

ios/brave-ios/Sources/BrowserMenu/BrowserMenu.swift

@@ -18,11 +18,20 @@ public struct BrowserMenu: View {
   /// Whether or not we may be viewing on a device that doesn't have as much horizontal space
   /// available (such as when Display Zoom is enabled)
   @State private var isHorizontalSpaceRestricted: Bool = false
+  @State private var activeActionHandlers: [Action.ID: Task<Void, Never>] = [:]
 
   @Environment(\.dynamicTypeSize) private var dynamicTypeSize
 
   private func handleAction(_ action: Binding<Action>) {
-    Task {
+    let id = action.wrappedValue.id
+    if activeActionHandlers[id] != nil {
+      // The action is in progress
+      return
+    }
+    let actionTask = Task {
+      defer {
+        activeActionHandlers[id] = nil
+      }
       let result = await action.wrappedValue.handler(action.wrappedValue)
       switch result {
       case .updateAction(let replacement):
@@ -34,6 +43,7 @@ public struct BrowserMenu: View {
         break
       }
     }
+    activeActionHandlers[id] = actionTask
   }
 
   private var numberOfQuickActions: Int {

ios/brave-ios/Sources/BrowserMenu/BrowserMenuModel.swift

@@ -86,7 +86,7 @@ import SwiftUI
   }
 
   func updateActionVisibility(_ action: Action, visibility: Action.Visibility) {
-    actionVisibility.value[action.id.id] = visibility == .visible ? true : false
+    actionVisibility.value[action.id.id] = visibility == .visible
     if visibility == .visible {
       // If the user is making a hidden item visible and the visible list is empty, we won't
       // give it an overridden rank to ensure it ends at the bottom

ios/brave-ios/Sources/BrowserMenu/Identifiers.swift

@@ -6,6 +6,27 @@
 import BraveWallet
 import Foundation
 
+/// The list of action identifiers
+///
+/// Every action that is shown in the menu must have an identifier created here so that it may be
+/// properly displayed and ordered in the new menu customization. The new menu should use every
+/// identifier that is usable even if the the action cannot be made in the current context so that
+/// user ordering & visibility is consistent.
+///
+/// **A note on rankings & visibility**:
+/// The new menu relies on 2 things for default item display: default ranking & default visibility.
+///
+/// Default rankings & visibility are currently based on a list in Figma and shouldn't be altered to
+/// ensure items don't move around on the user.
+///
+/// When a new menu item is added it should be given a new default ranking that isn't currently
+/// used. Currently all rankings are incremented by 100 to allow for new items to be added in
+/// between, so for example a new action identifier could be given a default rank of 175 if we
+/// wanted it to be placed second in the list if no user customization has occured or third in the
+/// list if it has (reordering sets overriden ranks based on the halfway point between items).
+///
+/// Default visibility controls whether or not the item appears on the menu without the user tapping
+/// "Show All…" to display all actions or explicitly adding it to the menu themselves.
 extension Action.Identifier {
 
   public static let vpn: Self = .init(

ios/brave-ios/Sources/BrowserMenu/VPNStatus.swift

@@ -28,7 +28,7 @@ struct VPNRegion: Equatable {
   }
 
   private static func flagEmojiForCountryCode(code: String) -> String {
-    // Root Unicode flags index
+    // Regional indicator symbol root Unicode flags index
     let rootIndex: UInt32 = 127397
     var unicodeScalarView = ""