Enum constants with class bodies as annotation values emit invalid code

[YangSiJun528]

Problem

When an enum constant with a class body is used as an annotation value, Annotation generates invalid source code and collects an import for the compiler-generated anonymous subclass instead of the declaring enum.

This occurs because getClass() returns the anonymous subclass for such constants. The added regression test demonstrates the resulting source code:

expected: "@Test(test = SpecializedEnum.SPECIALIZED)"
 but was: "@Test(test = .SPECIALIZED)"

Changes

• Use getDeclaringClass() instead of getClass() when generating enum values and collecting imports.
• Add a regression test covering both the generated source code and imports.

[mhalbritter]

Thanks @YangSiJun528 !