refactor(core): use the event loop proxy to send updater events (#3687)

* feat(core): add `WindowEvent::FileDrop`, closes #3664

* refactor(core): use the event loop proxy to send updater events

* simplify generics with user event trait

* fix tray impl

Author: lucasfernog

.changes/runtime-create-proxy.md

@@ -0,0 +1,6 @@
+---
+"tauri-runtime": minor
+"tauri-runtime-wry": minor
+---
+
+Added `create_proxy` to the `Runtime` and `RuntimeHandle` traits.

.changes/runtime-user-event.md

@@ -0,0 +1,6 @@
+---
+"tauri-runtime": minor
+"tauri-runtime-wry": minor
+---
+
+Allow specifying a user event type for the event loop message.

.changes/rust-tauri-events.md

@@ -0,0 +1,5 @@
+---
+"tauri": minor
+---
+
+**Breaking change:** The `tauri://` events are no longer emitted to listeners using `Window::listen`. Use the `App::run` closure, `Window::on_window_event` and `Window::on_menu_event` instead.

.changes/updater-events.md

@@ -0,0 +1,5 @@
+---
+"tauri": minor
+---
+
+Send updater events to the `App::run` closure.