Load JoinedRoom in home screen, pass it to the room flow (#5817)

* Load `JoinedRoom` in `HomeFlowNode.navigateToRoom`, then pass it to the next navigation nodes

* Add delayed loading indicator for cases when loading the room takes too long

* Avoid an extra FFI call in `RustRoomFactory`.

Use `RoomInfo.membership` instead.

Also use `computation` dispatcher, since it should reduce the delay when switching contexts.

* Remove the dispatcher usage when loading the room in `HomeFlowNode`, we immediately call a method that changes the dispatcher used

* Make sure only a single room is opened at a time

tests/uitests/build.gradle.kts

@@ -20,6 +20,11 @@ android {
     namespace = "ui"
 }
 
+tasks.withType(Test::class.java) {
+    // Don't fail the test run if there are no tests, this can happen if we run them with screenshot test disabled
+    failOnNoDiscoveredTests = false
+}
+
 dependencies {
     // Paparazzi 1.3.2 workaround (see https://github.com/cashapp/paparazzi/blob/master/CHANGELOG.md#132---2024-01-13)
     constraints.add("testImplementation", "com.google.guava:guava") {