test(migrate): verify canonical SQL-only version ordering

migrate/README.md

@@ -40,11 +40,19 @@ not defer it when sharing the pool with the application. Use `"."` for SQL files
 at the embedded root. Files in the selected directory are discovered directly,
 without recursively searching subdirectories.
 
-Use unique positive versions in filenames such as
-`20261027114500_create_users.sql`; sequential versions such as `00007_users.sql`
-also work. Never derive a version from a file count or add one to the current
-version. Keep applied migrations immutable and ship the complete history.
-Goose rejects newly introduced migrations below the current version by default.
+Use unique positive versions and Goose's migration creator naming convention:
+zero-padded sequential names such as `00007_users.sql` and `00010_events.sql`, or
+fixed-width timestamps such as `20261027114500_create_users.sql`. Filenames must
+sort lexically in numeric version order, including when mixing naming schemes;
+choose padding wide enough for the complete history. Goose v3.29.0 preserves
+lexical source order for SQL-only providers, so arbitrary unpadded names such as
+`7_users.sql` and `10_events.sql` are unsupported by this house convention: they
+can produce incorrect latest versions and source/status ordering. This package
+does not rename or normalize migration files.
+
+Never derive a version from a file count or add one to the current version.
+Keep applied migrations immutable and ship the complete history. Goose rejects
+newly introduced migrations below the current version by default.
 
 ```sql
 -- +goose Up