Define a plan feature once and the whole app follows
- Declare a feature in one place and the admin form, the billing page and the limits all follow, with no frontend work
- The billing page now leads with your plan and shows live usage meters for every feature, not just AI tokens
- Set a limit to -1 for unlimited, and switch AI on or off per plan tier, even for customers holding credits
- Plan JSON with missing keys or typos no longer breaks anything: limits fall back safely and the admin form warns you as you type
