Fix incorrect resolution of outer variable when method exists with the same name

[mppf]

Resolves #25551
Resolves #22918

This PR adjusts the way the new scope resolver handles looking for matches for methods in order to resolve problems with incorrect matches to methods interfering with finding an outer variable, which is the problem that occurs in #25551.

What is going wrong in #25551 is that the new scope resolver is 1) looking for the innermost match (for an identifier) and 2) searching first for methods from the definition point of myComparator and its parents. The result is to find the unrelated text method instead of the outer variable.

This PR resolves the problem by adjusting the scope resolution process to only consider methods that could be called when considering method receiver scopes.

Instead of pre-computing the receiver scopes and then checking these for methods, the lookup process now works with helper objects to call back into the scope resolution or full resolution process. There are two different helper objects for different purposes:

1. a MethodLookupHelper provides a way to access the scopes that should be checked for methods/fields and also provides a way to check if the receiver is applicable
2. a ReceiverScopeHelper provides a way to get a MethodLookupHelper that corresponds to the receiver type for a particular method ID (and at that point, the scopes from the MethodLookupHelper should be checked for applicable methods)

There are two implementations of each of these -- one that uses simplified rules and works without types (for use with the new scope resolution, which is currently enabled in production) -- and one that uses the full type system.

Reviewed by @benharsh - thanks!

• full comm=none testing