Foreign tables should be created using migrations, as we do for standard
tables.
Since those are not really generated from the object metadata but from
the remote table, those migrations won't live in the object metadata
service.
This PR:
- creates new types of migration : create_foreign_table and
drop_foreign_table
- triggers those migrations rather than raw queries directly
- moves the logic to fetch current foreign tables into the remote table
service since this is not directly linked to postgres data wrapper
- adds logic to unsync all tables before deleting
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Co-authored-by: Thomas Trompette <thomast@twenty.com>
