[IDE] Allow typeCheckASTNodeAtLoc to type check declarations
We need the ability to type check declarations when entering using `typeCheckASTNodeAtLoc` for solver-based cursor info.
This causes more context to be type checked for code completion and breaks some type completion after dot if the base type is not fully qualified because the type checker will mark `TypeRepr` as invalid. But since we don’t actually need to run the type checker for type member completion, we can just not call `typeCheckContextAt` for `TypeIdentifierWithDot` completions.
