Collect nested generic arguments when resolving type signatures

[arimu1]

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DefaultAotRepositoryContext.discoverTypes() collects reachable domain types via TypeCollector.inspect(…), which delegates to TypeUtils.resolveTypesInSignature. Cycle detection used the raw Class, so a nested parameterization of a type already seen (for example V in Map<K, Map<K, V>>) was skipped. One-level Map<K, V> was collected as expected.

This change visits generic arguments using the ResolvableType signature instead of the raw class, so nested component types are included in the AOT type set used for accessor generation.

TypeCollectorUnitTests.detectsTypesNestedMoreThanOneGenericLevel fails on current main (EmptyType2 missing) and passes with this change.

Closes #3530