Adopt Compound Colours (#1086)

* Delete deprecated font tokens.

* Migrate from primaryContent to textPrimary/iconPrimary.

* Migrate from links to textLinkExternal.

* Migrate from secondaryContent to textSecondary/iconSecondary.

* Migrate from accent to textActionPrimary.

- Some uses changed to textPrimary or iconPrimary as necessary.
- Some manual tints removed now that that Sentry is fixed.

* Migrate alert to textCriticalPrimary/iconCriticalPrimary.

* Migrate from brand to textActionAccent/iconAccentTertiary.

* Migrate from background to bgCanvasDefault or text/iconOnSolidPrimary

* Migrate system to bgSubtleSecondary.

* Remove ElementUIColors and obsolete migrated colours.

* Migrate tertiaryContent/quaternaryContent/quinaryContent to Compound.

* Migrate bubblesYou/bubblesNotYou to use Compound.

* Update Compound.

ElementX/Sources/Screens/StartChatScreen/View/StartChatScreen.swift

@@ -111,7 +111,7 @@ struct StartChatScreen: View {
     private var noResultsContent: some View {
         Text(L10n.commonNoResults)
             .font(.compound.bodyLG)
-            .foregroundColor(.element.tertiaryContent)
+            .foregroundColor(.compound.textSecondary)
             .frame(maxWidth: .infinity)
             .listRowBackground(Color.clear)
             .accessibilityIdentifier(A11yIdentifiers.startChatScreen.searchNoResults)
@@ -147,7 +147,6 @@ struct StartChatScreen_Previews: PreviewProvider {
     static var previews: some View {
         NavigationView {
             StartChatScreen(context: viewModel.context)
-                .tint(.element.accent)
         }
     }
 }