User-local settings (#20456)

...se/backend/src/metabase_enterprise/serialization/dump.clj

resources/migrations/000_migrations.yaml

src/metabase/api/card.clj

src/metabase/api/common.clj

src/metabase/api/common/validation.clj

src/metabase/api/dashboard.clj

src/metabase/api/embed.clj

src/metabase/api/preview_embed.clj

src/metabase/api/public.clj

src/metabase/driver.clj

src/metabase/driver/util.clj

src/metabase/models/setting.clj

src/metabase/models/user.clj

src/metabase/public_settings.clj

src/metabase/server/middleware/session.clj

test/metabase/models/setting_test.clj

test/metabase/server/middleware/session_test.clj