- migration writer now emits unique constraints (direct apply and live diff
previously dropped them); idempotent via the existing DO block
- unique constraint adopts a same-named model unique index with
ADD CONSTRAINT ... UNIQUE USING INDEX instead of building a second index
- dbml reader names unnamed unique indexes ukey_<table>_<cols> to match the
unique constraint naming
- foreign key deferral: Constraint.Deferrable/InitiallyDeferred are *bool
(nil = unspecified, never diffed); writers emit DEFERRABLE, DEFERRABLE
INITIALLY DEFERRED and NOT DEFERRABLE; live reader reads condeferrable and
condeferred; dbml reader/writer support deferrable and initially deferred
- tests and README/naming docs updated
warkanum
b4f18f088b