SpringBoot native fails /v3/api-docs when using a Map as an http entity field

[KlausCGM]

/v3/api-docs fails at runtime in native mode, omitting the entity, when a http entity with a Map is used

/swagger-ui/index.html, or, better say /v3/api-docs generates an incomplete open-api definition due to an exception.

I am using Spring boot 3.4.3 and springdoc 2.8.5.

To Reproduce

The entity:

DifficultClass.kt.txt

data class DifficultClass(
    val name: String,
    /**
     * properties can be anything mapping a string to Any
     */
    @Schema(example = """
        {"sequence": 123}
        """)
    val properties: Map<String, Any> = emptyMap()
)

The controller:

DifficultController.kt.txt

@RestController
@RequestMapping("/")
// the below register is a fix for swagger ui for native image. We could not find out the reason,
// but the class will cause a "Type not found" and leave the swagger screen in a half-ready state.
//@RegisterReflectionForBinding(java.lang.invoke.MethodHandles.Lookup::class)
class DifficultController {
    @PostMapping("a")
    @Operation(summary = "reproduce the problem")
    fun someFunction(@RequestBody problems: List<DifficultClass>) : DifficultClass? {
        return if (problems.isEmpty())
            null
        else
            problems.first()
    }
}

Resulting exception (only native)

nativeException.txt

Here is a project including test to reproduce:
swaggerNativeBugDemo.zip

use
./gradlew nativeTest
to reproduce.

The workaround is to register the java class for reflection as follows
@RegisterReflectionForBinding(java.lang.invoke.MethodHandles.Lookup::class)

Expected behavior

• The swagger should come up with a field for the request body the one controller method /a (which it does in non-native mode)
• No exception should be thrown

Screenshots
This is the screen that comes up in the case of native image without the reflection hint

Additional context: Workaround
The workaround, see above, is to register java.lang.invoke.MethodHandles.Lookup for the native image, but we don't know what is the underlying reason. I suspect it should be added to the springdoc provided spring-configuration-meadata.json in springdoc-openapi-starter-common-2.8.5.jar.

[KlausCGM]

Thank you!