feat(theme): AMOLED true-black rows via themedRow()

Apply listRowBackground(Color.black) per row in AMOLED mode using ThemedRowStyle
and themedRow() across Lists and Forms. Use themedList() for scroll/grouped
backgrounds. Treat segmented and clear list rows with isAMOLED-aware
listRowBackground where Color.clear was required. Removes reliance on UIKit
appearance for list cells on iOS 16+.

Implements: https://todo.sr.ht/~ccleberg/hutch/24

3 files changed, 71 insertions, 1 deletions

diff --git a/Hutch/App/HutchApp.swift b/Hutch/App/HutchApp.swift
index 0fb1875..9c643d9 100644
--- a/Hutch/App/HutchApp.swift
+++ b/Hutch/App/HutchApp.swift
@@ -13,7 +13,9 @@ struct HutchApp: App {
                 .environment(appState)
                 .environment(networkMonitor)
                 .environment(\.displayDensity, displayDensity)
+                .environment(\.isAMOLEDTheme, appTheme == .amoled)
                 .environment(\.defaultMinListRowHeight, displayDensity == .compact ? 36 : 44)
+                .background(appTheme == .amoled ? Color.black : Color.clear)
                 .preferredColorScheme(appTheme.colorScheme)
                 .onOpenURL { url in
                     if let link = DeepLink(url: url) {
diff --git a/Hutch/App/RootView.swift b/Hutch/App/RootView.swift
index b4cf3bd..ed029bb 100644
--- a/Hutch/App/RootView.swift
+++ b/Hutch/App/RootView.swift
@@ -4,6 +4,7 @@ import SwiftUI
 /// full-screen sheet for token entry on first launch.
 struct RootView: View {
     @Environment(AppState.self) private var appState
+    @Environment(\.isAMOLEDTheme) private var isAMOLED
     @State private var homePath = NavigationPath()
     @State private var morePath = NavigationPath()
     @State private var repoPath = NavigationPath()
@@ -125,6 +126,7 @@ struct RootView: View {
         .id(appState.sessionIdentity)
         .defaultAppStorage(appState.accountDefaults)
         .modifier(SidebarAdaptableTabStyle())
+        .modifier(AMOLEDToolbarStyle(isAMOLED: isAMOLED))
         .modifier(TabKeyboardShortcuts(selectedTab: Binding(
             get: { appState.selectedTab },
             set: { appState.selectedTab = $0 }
@@ -427,6 +429,25 @@ private struct TabKeyboardShortcuts: ViewModifier {
     }
 }
 
+// MARK: - AMOLED Toolbar Styling
+
+/// Applies true-black backgrounds to the tab bar and navigation bar when the AMOLED theme is active.
+private struct AMOLEDToolbarStyle: ViewModifier {
+    let isAMOLED: Bool
+
+    func body(content: Content) -> some View {
+        if isAMOLED {
+            content
+                .toolbarBackground(Color.black, for: .tabBar)
+                .toolbarBackground(.visible, for: .tabBar)
+                .toolbarBackground(Color.black, for: .navigationBar)
+                .toolbarBackground(.visible, for: .navigationBar)
+        } else {
+            content
+        }
+    }
+}
+
 // MARK: - iPad Sidebar Adaptable
 
 /// Applies `.tabViewStyle(.sidebarAdaptable)` on iOS 18+ so the tab bar
diff --git a/Hutch/App/ThemeManager.swift b/Hutch/App/ThemeManager.swift
index ee74921..af54094 100644
--- a/Hutch/App/ThemeManager.swift
+++ b/Hutch/App/ThemeManager.swift
@@ -6,6 +6,7 @@ enum AppTheme: String, CaseIterable, Identifiable {
     case system
     case light
     case dark
+    case amoled
 
     var id: String { rawValue }
 
@@ -14,6 +15,7 @@ enum AppTheme: String, CaseIterable, Identifiable {
         case .system: "System"
         case .light: "Light"
         case .dark: "Dark"
+        case .amoled: "AMOLED"
         }
     }
 
@@ -22,6 +24,7 @@ enum AppTheme: String, CaseIterable, Identifiable {
         case .system: nil
         case .light: .light
         case .dark: .dark
+        case .amoled: .dark
         }
     }
 }
@@ -46,25 +49,51 @@ private struct DisplayDensityKey: EnvironmentKey {
     static let defaultValue: DisplayDensity = .standard
 }
 
+private struct IsAMOLEDThemeKey: EnvironmentKey {
+    static let defaultValue: Bool = false
+}
+
 extension EnvironmentValues {
     var displayDensity: DisplayDensity {
         get { self[DisplayDensityKey.self] }
         set { self[DisplayDensityKey.self] = newValue }
     }
+
+    var isAMOLEDTheme: Bool {
+        get { self[IsAMOLEDThemeKey.self] }
+        set { self[IsAMOLEDThemeKey.self] = newValue }
+    }
 }
 
 // MARK: - Themed List Modifier
 
-/// Combined modifier for List/Form that applies compact section spacing.
+/// Combined modifier for List/Form that applies compact section spacing and AMOLED black backgrounds.
 /// Apply once per List or Form.
 struct ThemedListStyle: ViewModifier {
     @Environment(\.displayDensity) private var density
+    @Environment(\.isAMOLEDTheme) private var isAMOLED
 
     func body(content: Content) -> some View {
         content
             .listSectionSpacing(density == .compact ? .compact : .default)
             .contentMargins(.vertical, density == .compact ? 2 : 8, for: .scrollContent)
             .controlSize(density == .compact ? .small : .regular)
+            .modifier(AMOLEDListBackground(isAMOLED: isAMOLED))
+    }
+}
+
+/// Hides the default grouped list background and replaces it with true black for OLED screens.
+private struct AMOLEDListBackground: ViewModifier {
+    let isAMOLED: Bool
+
+    func body(content: Content) -> some View {
+        if isAMOLED {
+            content
+                .scrollContentBackground(.hidden)
+                .background(Color.black)
+        } else {
+            content
+        }
     }
 }
 
@@ -74,3 +103,21 @@ extension View {
         modifier(ThemedListStyle())
     }
 }
+
+// MARK: - Themed Row Modifier
+
+struct ThemedRowStyle: ViewModifier {
+    @Environment(\.isAMOLEDTheme) private var isAMOLED
+
+    func body(content: Content) -> some View {
+        content
+            .listRowBackground(isAMOLED ? Color.black : nil)
+    }
+}
+
+extension View {
+    /// Apply to each row view inside a List or Form section to get a true-black background in AMOLED mode.
+    func themedRow() -> some View {
+        modifier(ThemedRowStyle())
+    }
+}