Massively reorganize and clean up the whole Rust codebase (#478)

* Massively reorganize and clean up the whole Rust codebase

* Additional changes during code review

editor/src/input/input_preprocessor_message.rs

@@ -0,0 +1,22 @@
+use super::input_preprocessor::ModifierKeys;
+use super::keyboard::Key;
+use super::mouse::{EditorMouseState, ViewportBounds};
+use crate::message_prelude::*;
+
+#[doc(inline)]
+pub use graphene::DocumentResponse;
+
+use serde::{Deserialize, Serialize};
+
+#[remain::sorted]
+#[impl_message(Message, InputPreprocessor)]
+#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
+pub enum InputPreprocessorMessage {
+	BoundsOfViewports(Vec<ViewportBounds>),
+	KeyDown(Key, ModifierKeys),
+	KeyUp(Key, ModifierKeys),
+	MouseDown(EditorMouseState, ModifierKeys),
+	MouseMove(EditorMouseState, ModifierKeys),
+	MouseScroll(EditorMouseState, ModifierKeys),
+	MouseUp(EditorMouseState, ModifierKeys),
+}