Support underlying type extraction for Kotlin value classes in KSP codegen

[jbl428]

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Is your feature request related to a problem? Please describe.

Currently, when KSP codegen encounters a column whose type is a Kotlin value class,

it fails with an error similar to:

Error processing com.example.domain.Entity.fieldName: Type was not recognised, This may be an entity that has not been annotated with @Entity, or maybe you are using javax instead of jakarta.

It would be more useful if it used the underlying wrapped type instead.

Expected behavior:

@JvmInline
value class Email(
    val value: String
)

@Entity
class Person(
    @Id
    val id: Int,
    val email: Email,
)

public class QPerson : EntityPathBase<Person> {
    public val id: NumberPath<Int> = createNumber("id", kotlin.Int::class.javaObjectType)

    public val email: StringPath = createString("email")
}

Describe the solution you'd like

Make TypeExtractor.kt consider kotlin value class and return KSType as inner type