Add crash-safe attempt authority lifecycle

crates/remora-attempt/src/migrate.rs

@@ -0,0 +1,12 @@
+use sqlx::PgPool;
+
+use crate::AttemptError;
+
+pub async fn migrate(pool: &PgPool) -> Result<(), AttemptError> {
+    let mut migrator = sqlx::migrate!("./migrations");
+    migrator.dangerous_set_table_name("_remora_attempt_migrations");
+    migrator
+        .run(pool)
+        .await
+        .map_err(|error| AttemptError::Durable(remora_durable::DurableError::Migrate(error)))
+}