Unload scene specific resources on demand

[ViktorVovk]

This is an implementation of functionality for unloading all resources from the scene we are leaving. For example, we have several scenes (Preloader, postPreloader) that contain a significant number of resources such as images, audio, spine animations, atlases, JSON files, and so on. After these scenes have been loaded, once we transition to the so-called main scene, we want to remove (unload) all resources from the scenes that we do not expect to return to during the game’s runtime.

Plan for implementing the unloading of scene-specific resources on the GDevelop side:

1. An additional boolean parameter needs to be added to the "change scene" action. Enabling this parameter will indicate that all resources specific to the scene being exited should be unloaded. It is assumed that we will not return to this scene during the game’s runtime.

2. During the execution of the "change scene" action, the _destroy method is eventually called on the scene object (in runtimescene.ts). At that point, the resource cleanup method disposeScene—implemented in the ResourceLoader class—is invoked.

3. The disposeScene method accepts the scene name as a parameter and creates a Map where the keys are resource types (ResourceKind) and the values are arrays of ResourceData.

4. In the ResourceLoader class, there is a field _resourceManagersMap where the keys are resource types (ResourceKind) and the values are resource managers. This makes it easy to correlate this map with the map of resources grouped by type since they share the same keys.

5. In each resource manager class, a method disposeByResourcesList has been implemented, which takes an array of resources that need to be cleared. This method performs the cleanup of the resources in the provided list.