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Also refactor damus app usage to only pass in things that we need in views.

Signed-off-by: William Casarin <jb55@jb55.com>

src/ui/mod.rs

@@ -31,7 +31,9 @@ pub use username::Username;
 use egui::Margin;
 
 /// This is kind of like the Widget trait but is meant for larger top-level
-/// views that are typically stateful. The Widget trait forces us to add mutable
+/// views that are typically stateful.
+///
+/// The Widget trait forces us to add mutable
 /// implementations at the type level, which screws us when generating Previews
 /// for a Widget. I would have just Widget instead of making this Trait otherwise.
 ///