Lagrange.OneBot.DatabaseShift --helpLagrange.OneBot.DatabaseShift --in /path/to/lagrange-0.dbThe output Realm database folder will be located at /path/to/lagrange-0-db.
Checkout the branch of the submodule Lagrange.OneBot to the corresponding branch that uses LiteDB, modify RealmMessageRecord to ensure all desired fields are stored, then compile and run it.