Allow replacing the default implementations of the cache manager and storage

[AlexV525]

1. The interface of the storage has been extracted from the default implementation. Users can implement their own instead of using Get Storage or Shared Preferences.
2. The default fields can be updated instead of final.

[OutdatedGuy]

Mostly LGTM, few questions and changes.

[AlexV525]

I've made a couple of changes additionally:

1. The storage interface was extracted with a more general interface that can be used to store any type of data.
2. I've renamed VideoPlayerStorage to VideoPlayerMetadataStorage and made a type alias to deprecate VideoPlayerStorage, but I think we can safely remove it since the class was not exported directly before.

[AlexV525]

@OutdatedGuy friendly ping

[OutdatedGuy]

LGTM! Will once check updated example app and then merge.

Thanks for the contribution!

[OutdatedGuy]

Screen.Recording.2025-10-04.at.12.39.48.PM.mov

@AlexV525 the example app doesn't seems to be working correctly