update platform lock for rocksdb migration

[rafapaezbas]

Blocked by holepunchto/pear#638

[Copilot]

Pull Request Overview

This PR updates the platform lock constant to support migration for RocksDB.

• Changes the file path from 'corestores/platform/primary-key' to 'corestores/platform/LOCK'
• Updates the PLATFORM_LOCK constant accordingly in constants.js

Comments suppressed due to low confidence (1)

constants.js:27

• Verify that the new file name 'LOCK' complies with the project's naming conventions and that all corresponding references have been updated as part of the migration. Consider adding a brief comment if needed to clarify the change for future maintainers.

const PLATFORM_LOCK = toPath(new URL('corestores/platform/LOCK', PLATFORM_URL))