[9.x] Improves Cache facade types

[nunomaduro]

This pull request improves Cache facade types, as initial proposed by #45325. So, the following types are correctly inferred by PHPStan, and hopefully, in the future, by PHPStorm:

Cache::get('key')); // mixed
Cache::get('key', 1)); // int
Cache::get('key', fn () => 1); // int

Cache::pull('key')); // mixed
Cache::pull('key', 1)); // int
Cache::pull('key', fn () => 1); // int

Cache::sear('key', fn () => 1); // int
Cache::remember('key', now(), fn () => 1); // int
Cache::rememberForever('key', fn () => 1); // int