fix(exo)!: extra undeclared args dropped

[erights]

Alternative to #1764 experiment.

Of the options listed there, this one

Preserve the tolerant behavior, but not pass the values of the extra args through to the protected raw behavior method. This would preserve the input validation intent of method guards while still accommodating API growth and thus version slippage.

As suggested by @mhofman and @turadg

[erights]

Reviewers,

I made this a fix(exo)!: rather than a fix(exo): because it technically is a compat break. However, it is unlikely to currently be a compat break in practice, so let me know if you think I should remove the !.

[turadg]

I agree that a) this is technically a breaking change and b) it's unlikely to break anything.

Since the package version hasn't reached 1.0, there's little downside to making a breaking change. So I think keep the ! to err on the side of being loud about it.

[mhofman]

LGTM