feat: add native-like page transitions for Android

- Added `RouteTransitions` utility.
- Configured TanStack Router `defaultViewTransition`.
- Added `transitions.css` with push/pop animations.
- Wired up Android back button in `App.tsx`.
- Added `tauri-plugin-app` to backend to ensure back button event works.
- Added documentation and unit tests.

Author: google-labs-jules[bot]

apps/window-alarm/src-tauri/Cargo.toml

@@ -15,6 +15,7 @@ tauri-build = { version = "2.0.0", features = [] }
 tauri = { version = "2.0.0", features = [] }
 log = "0.4"
 tauri-plugin-sql = { version = "2.0.0", features = ["sqlite"] }
+tauri-plugin-app = { version = "2.0.0", features = [] }
 tauri-plugin-alarm-manager = { path = "../../../plugins/alarm-manager" }
 tauri-plugin-deep-link = { version = "2.0.0", features = [] }
 tauri-plugin-log = { version = "2.0.0", features = [] }

apps/window-alarm/src-tauri/src/lib.rs

@@ -60,6 +60,7 @@ pub fn run() {
 
     builder
         .plugin(tauri_plugin_sql::Builder::default().build())
+        .plugin(tauri_plugin_app::init())
         .plugin(tauri_plugin_alarm_manager::init())
         .plugin(tauri_plugin_deep_link::init())
         .plugin(tauri_plugin_notification::init())

apps/window-alarm/src/router.tsx

@@ -85,7 +85,7 @@ const routeTree = rootRoute.addChildren([indexRoute, homeRoute, editAlarmRoute,
 export const router = createRouter({
     routeTree,
     defaultNotFoundComponent: NotFound,
-    defaultViewTransition: ({ location }) => {
+    defaultViewTransition: (({ location }: { location: any }) => {
         // 1. Check if allowed
         if (!routeTransitions.shouldAnimate()) {
              return false;
@@ -109,7 +109,7 @@ export const router = createRouter({
         return {
             types: ['wa-slide', `wa-${direction}`]
         };
-    }
+    }) as any
 });
 
 declare module '@tanstack/react-router' {