[9.x] Improve Support\LazyCollection type definitions

[sebdesign]

Similarly to #38538, this PR makes the LazyCollection generic.

I haven't tested this with PHPStorm or Psalm, but in VSCode + PHPStan extension it works great.

Also:

• Fixed some minor issues with the Support\Collection types
• Added missing tests for some methods

There are still a few issues with the constructors and the make() method of the collections:

• The Support\LazyCollection needs to widen the type of items it accepts, because it accepts callables that return Generators, but the Support\Collection does not accept that. I have extended the make method and it works as expected.

• For some reason new Eloquent\Collection([new User()]) returns Eloquent\Collection<(int|string), Eloquent\Model> instead of Eloquent\Collection<int, User>. If I extend the constructor it works (but I haven't included this).

[driesvints]

Seems like tests are failing here. Feel free to markt his as ready when tests are passing.

[sebdesign]

All good now! Maybe @nunomaduro would like to review this?

[driesvints]

Ping @JosephSilber

[sebdesign]

Also, @JosephSilber I think there is an issue with the internal types the LazyCollection: The makeIterator returns a Traversable but it is used as if it's an Iterator.