Add support for MapsId annotation

I can't make @MapsId work using Micronaut data JDBC and Kotlin.

SQL schema :

CREATE TABLE user_account (
    id BIGINT NOT NULL PRIMARY KEY,
    username VARCHAR(255) NOT NULL,
);
CREATE TABLE user_tokens (
    id BIGINT NOT NULL PRIMARY KEY REFERENCES user_account(id),
    access_token VARCHAR(255) NOT NULL,
    refresh_token VARCHAR(255) NOT NULL,
    expiration_date TIMESTAMP NOT NULL
);

Kotlin classes :

import javax.persistence.*

@Entity
data class UserAccount(
        @Id
        val id: Long,
        @Column(nullable = false)
        val username: String
)

@Entity
data class UserTokens(
        @Id
        val id: Long,
        @MapsId
        @OneToOne
        val user: UserAccount,
        @Column(nullable = false)
        val accessToken: String,
        @Column(nullable = false)
        val refreshToken: String,
        @Column(nullable = false)
        val expirationDate: Date
)

Repositories :

@JdbcRepository
interface UserAccountRepository : CrudRepository<UserAccount, Long>
@JdbcRepository
interface UserTokensRepository : CrudRepository<UserTokens, Long>

Inserting a new user account works well, but when trying to insert some associated tokens, SQL query is generated using a user_id property I do not expect here.

io.micronaut.data.exceptions.DataAccessException: SQL Error executing INSERT: Colonne "USER_ID" non trouvée
Column "USER_ID" not found; SQL statement:
INSERT INTO user_tokens (user_id,access_token,refresh_token,expiration_date,id) VALUES (?,?,?,?,?) [42122-199]

I'm expecting the target SQL request to be
INSERT INTO user_tokens (access_token,refresh_token,expiration_date,id) VALUES (?,?,?,?)
Since @MapsId + @OneToOne should just declare a primary + foreign key.

Start by reproducing the issue with the Kotlin UserAccount and UserTokens entities, the @MapsId and @OneToOne annotations, and the two JDBC repositories shown here. Trace the generated INSERT for user_tokens and the handling of @MapsId; done means it no longer references the nonexistent user_id column and matches the stated schema.