Rework contracts to be compatible with spatie/ignition

[AlexVanderbist]

No description provided.

[CodeSkills]

Will this be merged any time soon? We are using this and would love to upgrade to laravel 9, so if we should wait for this to get merged or to migrate whole code to spatie/laravel-ignition directly?

Thanks for the update!

[stancl]

Does this PR mean ignition-contracts will always depend on ignition?

I see that there are differences in the namespaces (Spatie\ vs Facade\), but parts of the code, such as class BaseSolution extends \Spatie\Ignition\Contracts\BaseSolution implements Solution, make it seem that way. But I think the dependency should be in the opposite direction?

[PaolaRuby]

@stancl yes, but they are trying to leave development of this package behind so ignition will be the main fork, this PR is for compatibility with older apps