Migration filenames now follow the pattern <version>_<description>.sql
(e.g. 001_initial_schema.sql). The version stored in schema_migrations
is the numeric prefix only, not the full filename stem.
Changes:
- Add ParseMigrationVersion() to extract numeric prefix from filenames
- Validate version is purely numeric, reject malformed filenames
- Rename 001.sql to 001_initial_schema.sql for clarity
- Deduplicate runMigrations/ApplyMigrations via shared applyMigrations()
- Add comprehensive unit tests for version parsing and migration apply
Closes#28
