exposures do not play nice with meshify

[dave-connors-3]

Describe the bug

Report from a customer that exposures "break with meshify" -- this ticket is a stub to investigate. Hunch is that this is on the split operation

Additional context

Are you interested in contributing the fix?

[dave-connors-3]

Steps I took to test:

Add an exposure and split it with other models

1. Add an exposure called crazy_growth_dashboard to the split project, dependent on only the orders model
2. run dbt-meshify split dave_test --select "+orders exposure:crazy_growth_dashboard
3. Result: ✅ -- everything moved as expected

Add an exposure and leave it behind

1. Add an exposure called crazy_growth_dashboard to the split project, dependent on only the orders model
2. run `dbt-meshify split dave_test --select +orders
3. Result: ✅ -- everything moved as expected (even though the exposure is not dependent on models elsewhere)
4. thought: perhaps this is the issue? that refs should be rewritten if you have an exposure now dependent on public model in another project?