Add highlighter extension

This commit adds a highlighting extension for web pages. This works on
Safari, and can be used by selecting a text on a page and hitting the
share button at the bottom of the Safari UI

To make this possible, some refactoring was necessary:
1. Several sources were included in the extension bundle to provide access to DamusState, PostView, and the postbox
2. UIApplication.shared was replaced with `this_app`, which routes to UIApplication.shared on the main app bundle,
   and routes to a bogus UIApplication() in the extension. This is needed because UIApplication.shared cannot be used on an extension.
3. Some items were moved to different files to facilitate the transition.

The extension itself uses PostView, and implements views for several edge cases, and tries to handle the note publishing process gracefully.

Changelog-Added: Add highlighter for web pages
Signed-off-by: Daniel D’Aquino <daniel@daquino.me>

damus/Components/InvoiceView.swift

@@ -94,8 +94,8 @@ enum OpenWalletError: Error {
 }
 
 func open_with_wallet(wallet: Wallet.Model, invoice: String) throws {
-    if let url = URL(string: "\(wallet.link)\(invoice)"), UIApplication.shared.canOpenURL(url) {
-        UIApplication.shared.open(url)
+    if let url = URL(string: "\(wallet.link)\(invoice)"), this_app.canOpenURL(url) {
+        this_app.open(url)
     } else {
         guard let store_link = wallet.appStoreLink else {
             throw OpenWalletError.no_wallet_to_open
@@ -105,11 +105,11 @@ func open_with_wallet(wallet: Wallet.Model, invoice: String) throws {
             throw OpenWalletError.store_link_invalid
         }
         
-        guard UIApplication.shared.canOpenURL(url) else {
+        guard this_app.canOpenURL(url) else {
             throw OpenWalletError.system_cannot_open_store_link
         }
         
-        UIApplication.shared.open(url)
+        this_app.open(url)
     }
 }
 
@@ -122,8 +122,3 @@ struct InvoiceView_Previews: PreviewProvider {
             .frame(width: 300, height: 200)
     }
 }
-
-
-func present_sheet(_ sheet: Sheets) {
-    notify(.present_sheet(sheet))
-}

damus/ContentView.swift

@@ -57,6 +57,10 @@ enum Sheets: Identifiable {
     }
 }
 
+func present_sheet(_ sheet: Sheets) {
+    notify(.present_sheet(sheet))
+}
+
 struct ContentView: View {
     let keypair: Keypair
     let appDelegate: AppDelegate?
@@ -877,7 +881,7 @@ func update_filters_with_since(last_of_kind: [UInt32: NostrEvent], filters: [Nos
 
 
 func setup_notifications() {
-    UIApplication.shared.registerForRemoteNotifications()
+    this_app.registerForRemoteNotifications()
     let center = UNUserNotificationCenter.current()
     
     center.getNotificationSettings { settings in

damus/Models/Camera/CameraService.swift

@@ -151,7 +151,7 @@ public class CameraService: NSObject, Identifiable {
 
             DispatchQueue.main.async {
                 self.alertError = AlertError(title: "Camera Access", message: "Damus needs camera and microphone access. Enable in settings.", primaryButtonTitle: "Go to settings", secondaryButtonTitle: nil, primaryAction: {
-                        UIApplication.shared.open(URL(string: UIApplication.openSettingsURLString)!,
+                        this_app.open(URL(string: UIApplication.openSettingsURLString)!,
                                                   options: [:], completionHandler: nil)
 
                 }, secondaryAction: nil)

damus/Util/DamusAliases.swift

@@ -0,0 +1,11 @@
+//
+//  DamusAliases.swift
+//  damus
+//
+//  Created by Daniel D’Aquino on 2024-08-12.
+//
+
+import Foundation
+import UIKit
+
+let this_app: UIApplication = UIApplication.shared

damus/Util/InputDismissKeyboard.swift

@@ -30,7 +30,7 @@ public struct DismissKeyboardOnTap: ViewModifier {
 }
 
 public func end_editing() {
-    UIApplication.shared.connectedScenes
+    this_app.connectedScenes
       .filter {$0.activationState == .foregroundActive}
       .map {$0 as? UIWindowScene}
       .compactMap({$0})

damus/Util/Theme.swift

@@ -11,8 +11,7 @@ import UIKit
 class Theme {
     
     static var safeAreaInsets: UIEdgeInsets? {
-        return UIApplication
-                .shared
+        return this_app
                 .connectedScenes
                 .flatMap { ($0 as? UIWindowScene)?.windows ?? [] }
                 .first { $0.isKeyWindow }?.safeAreaInsets

damus/Views/AddRelayView.swift

@@ -116,7 +116,7 @@ struct AddRelayView: View {
                 }
                 new_relay = ""
 
-                UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
+                this_app.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
                 
                 dismiss()
             }) {

damus/Views/Muting/AddMuteItemView.swift

@@ -87,7 +87,7 @@ struct AddMuteItemView: View {
 
                 new_text = ""
 
-                UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
+                this_app.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
 
                 dismiss()
             }) {

damus/Views/Notifications/DamusAppNotificationView.swift

@@ -96,7 +96,7 @@ struct DamusAppNotificationView: View {
         
         @MainActor
         func open_url(url: URL) {
-            UIApplication.shared.open(url)
+            this_app.open(url)
         }
         
         var body: some View {

damus/Views/Zaps/CustomizeZapView.swift

@@ -356,7 +356,7 @@ struct ZapSheetViewIfPossible: View {
 extension View {
     func hideKeyboard() {
         let resign = #selector(UIResponder.resignFirstResponder)
-        UIApplication.shared.sendAction(resign, to: nil, from: nil, for: nil)
+        this_app.sendAction(resign, to: nil, from: nil, for: nil)
     }
 }