Compound - Swift 6.2 and Main actor isolation (#5109)

* compound is now using 6.2 and main actor isolation + some tweaks to make it build tests and EX

* better handling of the nonisolated context for CompoundUIColors

* improving docs

* fix comment

* remove unused Sendable conformance

ElementX/Sources/Screens/Timeline/View/ItemMenu/TimelineItemMenu.swift

@@ -243,6 +243,7 @@ private struct VerifiedUserSendFailureView: View {
     }
 }
 
+@MainActor
 private extension EncryptionAuthenticity {
     var foregroundStyle: SwiftUI.Color {
         switch color {

ElementX/Sources/Screens/Timeline/View/Style/TimelineItemBubbleBackground.swift

@@ -16,10 +16,10 @@ extension View {
     ///   - color: self explanatory, defaults to subtle secondary
     func bubbleBackground(isOutgoing: Bool = true,
                           insets: EdgeInsets = .init(top: 8, leading: 12, bottom: 8, trailing: 12),
-                          color: Color? = .compound.bgSubtleSecondary) -> some View {
+                          color: @autoclosure @MainActor () -> Color? = .compound.bgSubtleSecondary) -> some View {
         modifier(TimelineItemBubbleBackgroundModifier(isOutgoing: isOutgoing,
                                                       insets: insets,
-                                                      color: color))
+                                                      color: color()))
     }
 }
 

ElementX/Sources/Screens/Timeline/View/Style/TimelineItemBubbledStylerView.swift

@@ -238,6 +238,7 @@ struct TimelineItemBubbledStylerView<Content: View>: View {
     }
 }
 
+@MainActor
 private extension EventBasedTimelineItemProtocol {
     var bubbleBackgroundColor: Color? {
         let defaultColor: Color = isOutgoing ? .compound._bgBubbleOutgoing : .compound._bgBubbleIncoming

ElementX/Sources/Screens/Timeline/View/Style/TimelineItemSendInfoLabel.swift

@@ -112,6 +112,7 @@ private struct TimelineItemSendInfoLabel: View {
 }
 
 /// All the data needed to render a timeline item's send info label.
+@MainActor
 private struct TimelineItemSendInfo {
     enum Status {
         case sendingFailed
@@ -185,6 +186,7 @@ private extension TimelineItemSendInfo {
     }
 }
 
+@MainActor
 private extension EncryptionAuthenticity {
     var foregroundStyle: SwiftUI.Color {
         switch color {