unlockable variables

- add unlockable vars
- make it generic for multiple vars
- make the unlock condition generic
- help text from Aude when an unlockable variable is unlocked

No files or tests are listed. Start by finding where unlockable variables and unlock-condition logic live in the TypeScript game flow, then identify how unlock events emit help text. Make the unlock handling support multiple variables through a generic condition path, and reuse that path to trigger Aude’s unlock message. Validate by running the relevant tests (or project run) for unlock scenarios and confirming the generic path still displays the help text correctly for multiple unlocks.

索引モデルが issue の本文から書いたものです。