SQLite enum-ish column support.

[igalklebanov]

Hey 👋

SQLite doesn't have native enum type support. However, it is not uncommon to see usage of column text check(column in (...)) in table definitions. We could improve UX by parsing these and mapping to options and enum input group.

[sorenbs]

Hey @igalklebanov 👋 Still a good idea — text check(col in ('a','b')) is the de-facto enum pattern in SQLite and mapping it to the enum input group would be a genuine UX win. Requires parsing CHECK constraints out of sqlite_master table SQL, so slightly more involved than #1386, but well-scoped. Keeping open.