When calling m.update(parameters: ..., verify: .all) on a module, there is no check that is performed to ensure that all the parameters under m have been set. This has bitten me a couple times when porting a model to mlx-swift, and I think it's related to this todo in Module.swift.

This PR adds some support to check also for this. A couple comments:

• Most of the change is in the recursive call to .apply where the .value can be .none for the case where we don't have anything in the parameters but have to go through the modules to check that there is no parameter to be set.
• When handling the .dictionary case , the iteration has been changed so that we ensure to go over all the model items rather than going through all the parameters.
• This modifies the default behavior so it's a breaking change. Another possibility could be to set .all not to include the new .allModelKeysSet and have a new .strict flag that is .all + .allModelKeysSet.
• This only affects the parameters update, not the update with modules.
• A dedicated test has been added.

Any feedback on this is very welcome.