Multiple `autoincrement` counters in a database

A customer heavily uses `autoincrement` keys because that's what the framework Laravel does by default. This is the same with SQLAlchemy. To facilitate `autoincrement` keys working with branches in normal use cases, currently, we share an `autoincrement` counter among branches of a table.

However, this runs afoul of the customer isolation use case, where you have a single database, shared schema and domain tables on `main` but have customer specific data on each branch. In this case, `autoincremnt` `id`s get commingled among customers. This may be ok for some but is especially hard for migration where there will be multiple `id`s shared among branches, confusing things.

There are a few things we can do:

1. Make shared `autoincrement` a database, table, and/or branch level configuration.
2. Make named/namespaced `autoincrement` counters that are shared

Other ideas welcome here.