Closes #836

Summary of what was implemented (everything is analogous to existing applyMigrationsDuringBuild):

1. Types

• Added applyMigrationsDuringDev?: boolean to DatabaseConfig with JSDoc (@default true).
• Added applyMigrationsDuringDev: boolean to ResolvedDatabaseConfig.

1. Default

• Set default applyMigrationsDuringDev: true in the defu config in resolveDatabaseConfig.

1. Dev plugin

• Added early return: if (!hub.db.applyMigrationsDuringDev) return so migrations are skipped when the option is false.

1. Tests

• Included applyMigrationsDuringDev: true in the default SQLite test.
• Added “should respect custom applyMigrationsDuringDev” test for applyMigrationsDuringDev: false.
• In the D1 test, asserted applyMigrationsDuringDev stays true (D1 does not force it to false).

1. Docs

• docs/content/docs/2.database/4.migrations.md: Extended the note to describe applyMigrationsDuringDev and showed both options in the example.
• docs/content/docs/2.database/1.index.md: In the Docker/Kubernetes section, updated the intro and added applyMigrationsDuringDev: false to the SQLite, PostgreSQL, and MySQL examples.

All tests pass, and there are no linter errors.