fix: rerun migrations when mysql starts

[harshapalnati]

• Added helpers to stream each .
• sql migration into the running MySQL container (runMysqlScript + applyMysqlMigrations), and updated the MySQL startup logic so every tsbx start run waits for the DB (whether newly created or restarted) and reapplies the SQL files from db/migrations.
• This keeps Docker-based setups in sync even though raw DB files aren’t bundled with the image.