fix: store refresh-at as string type, not date type, for sqlx autotyping

migrations/each_user/0012_contact_fresh_type.sql

@@ -1,5 +1,12 @@
+-- foreign_keys can only up/down outside of transactions
+-- so we first pre-commit the one started by sqlx...
+COMMIT TRANSACTION;
 
+-- turn off foreign keys...
 PRAGMA foreign_keys=OFF;
+
+-- start our own transaction...
+BEGIN TRANSACTION;
 create table if not exists new_contacts (
 	id integer primary key autoincrement,
 	birthday text,
@@ -16,4 +23,12 @@ insert into new_contacts (
 drop table contacts;
 alter table new_contacts rename to contacts;
 PRAGMA foreign_key_check;
+
+-- commit our own transaction...
+COMMIT TRANSACTION;
+
+-- put our own pragmas back...
 PRAGMA foreign_keys=ON;
+
+-- and start a dummy transaction so sqlx's COMMIT doesn't explode
+BEGIN TRANSACTION;