Fix issue with runtime resolve on open generic class

[PhenX]

No description provided.

[Copilot]

Pull request overview

This PR fixes a runtime resolution issue in ProjectionExpressionResolver when resolving [Projectable] members on closed generic type instantiations by ensuring parameter-type name generation is based on the member as declared on the generic type definition (matching the source generator’s naming).

Changes:

• Update runtime reflection-based resolver logic to inspect methods/constructors as declared on the generic type definition when the declaring type is normalized to an open generic definition.
• Add runtime regression tests that mimic generated expression factory types in the test assembly and validate reflection resolution + resolved lambda signatures.
• Add/extend generator snapshot coverage for generic-class methods whose parameters are the class type parameter.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
tests/EntityFrameworkCore.Projectables.Tests/Services/ProjectionExpressionResolverGenericTypeTests.cs	Adds runtime regression tests and hand-crafted “generated” classes to validate reflection resolution on closed generic types.
tests/EntityFrameworkCore.Projectables.Generator.Tests/GenericTests.GenericClassMethodsWithTypeParameterParameter.verified.txt	Adds the verified snapshot for generated output of a generic-class method taking the class type parameter.
tests/EntityFrameworkCore.Projectables.Generator.Tests/GenericTests.cs	Adds a generator regression test to exercise generic-class methods with type-parameter parameters.
src/EntityFrameworkCore.Projectables/Services/ProjectionExpressionResolver.cs	Adjusts reflection resolver to compute parameter type names from the member on the generic type definition (method/ctor).