Fix pressing CW button in Compose not toggling field visibility

Bring back the wrapper view, turn's out it was load bearing. We need to
be able to observe both the ui state and the draft object, while also
updating the observed draft object when the ui state's draft changes,
and this seems like the most straightforward way of doing that.

Tusker/Screens/Compose/ComposeHostingController.swift

@@ -16,7 +16,7 @@ protocol ComposeHostingControllerDelegate: AnyObject {
     func dismissCompose(mode: ComposeUIState.DismissMode) -> Bool
 }
 
-class ComposeHostingController: UIHostingController<ComposeView>, DuckableViewController {
+class ComposeHostingController: UIHostingController<ComposeHostingController.Wrapper>, DuckableViewController {
     
     weak var delegate: ComposeHostingControllerDelegate?
     weak var duckableDelegate: DuckableViewControllerDelegate?
@@ -36,11 +36,11 @@ class ComposeHostingController: UIHostingController<ComposeView>, DuckableViewCo
         
         self.uiState = ComposeUIState(draft: realDraft)
         
-        let compose = ComposeView(
+        let wrapper = Wrapper(
             mastodonController: mastodonController,
             uiState: uiState
         )
-        super.init(rootView: compose)
+        super.init(rootView: wrapper)
         
         self.uiState.delegate = self
         
@@ -129,6 +129,23 @@ class ComposeHostingController: UIHostingController<ComposeView>, DuckableViewCo
     
 }
 
+extension ComposeHostingController {
+    struct Wrapper: View {
+        let mastodonController: MastodonController
+        @ObservedObject var uiState: ComposeUIState
+        var draft: Draft {
+            uiState.draft
+        }
+        
+        var body: some View {
+            ComposeView()
+                .environmentObject(mastodonController)
+                .environmentObject(uiState)
+                .environmentObject(draft)
+        }
+    }
+}
+
 extension ComposeHostingController: ComposeUIStateDelegate {
     var assetPickerDelegate: AssetPickerViewControllerDelegate? { self }
     

Tusker/Screens/Compose/ComposeView.swift

@@ -42,11 +42,9 @@ import Combine
 }
 
 struct ComposeView: View {
-    @ObservedObject var mastodonController: MastodonController
+    @EnvironmentObject var mastodonController: MastodonController
-    @ObservedObject var uiState: ComposeUIState
+    @EnvironmentObject var uiState: ComposeUIState
-    var draft: Draft {
+    @EnvironmentObject var draft: Draft
-        uiState.draft
-    }
     
     @State private var globalFrameOutsideList: CGRect = .zero
     @State private var contentWarningBecomeFirstResponder = false
@@ -62,11 +60,6 @@ struct ComposeView: View {
     
     private let stackPadding: CGFloat = 8
     
-    init(mastodonController: MastodonController, uiState: ComposeUIState) {
-        self.mastodonController = mastodonController
-        self.uiState = uiState
-    }
-    
     private var charactersRemaining: Int {
         let limit = mastodonController.instanceFeatures.maxStatusChars
         let cwCount = draft.contentWarningEnabled ? draft.contentWarning.count : 0
@@ -84,12 +77,6 @@ struct ComposeView: View {
     }
     
     var body: some View {
-        bodyWithoutEnvironment
-            .environmentObject(uiState)
-            .environmentObject(mastodonController)
-    }
-    
-    private var bodyWithoutEnvironment: some View {
         ZStack(alignment: .top) {
             mainList
                 .scrollDismissesKeyboardInteractivelyIfAvailable()
@@ -173,7 +160,7 @@ struct ComposeView: View {
                 .listRowInsets(EdgeInsets(top: draft.inReplyToID == nil ? 8 : 4, leading: 8, bottom: 4, trailing: 8))
                 .listRowSeparator(.hidden)
             
-            if draft.contentWarningEnabled {
+            if uiState.draft.contentWarningEnabled {
                 ComposeEmojiTextField(
                     text: $uiState.draft.contentWarning,
                     placeholder: "Write your warning here",