[ENHANCEMENT] Make Nurikabe Finish Room a bit more general

[Bram28]

Describe the current behavior of what you're trying to improve. If your enhancement request related to a problem, please also describe the problem.

Right now the Finish Room Case Rule in Nurikabe only applies to rooms that require exactly one more white cell.

Describe the improvement you'd like

It would be nice if the rule could be applied to rooms where any number of whites are still needed.

Of course, the number of possibilities could quickly explode, but we have a maximum number of branches that a case rule could go into, so if it is too many, it won;t allow you ... but it should work for room for which there are, say, 4 options to add the last 2 whites.

I also get the impression that the rule as it currently is implemented, does not create branches that immediately run into a different room, i.e. the rule takes into account black and white squares. I that is fine ... and that will also cut down on the number of possibilities, so all the more reason to generalize this rule a bit.

I also notice the rule is not listed in the Wiki yet .. someone please do so ... and please provide a precise description of how the rule works.

Describe alternatives you've considered

No response

Additional Context

No response