saveIfNotExistsAndGet
fun saveIfNotExistsAndGet(entity: T, serialConsistency: KandraConsistency = KandraConsistency.LOCAL_SERIAL): T?
Same LWT write as saveIfNotExists, but returns the entity actually persisted — including any @GeneratedUuid/@CreatedAt/@UpdatedAt values generated for the write, which saveIfNotExists computes internally and then discards behind a bare Boolean. Returns null when the row already existed (the same case saveIfNotExists reports as false) — use this whenever the caller needs the real generated values on the success path, e.g. to build an HTTP response, instead of the placeholder ones on the object it constructed. See GH #138 (same root-cause shape as GH #132 / saveAndGet()).