feat: expose secrets API for browser-based management #10
Description
Problem
AI features require AI_API_KEY and AI_PROVIDER as project secrets. These can only be set via CLI (run402 secrets set). The Wild Lychee admin settings panel had to show CLI instructions instead of a working "Save" button.
Suggested Solution
Expose a secrets API that authenticated project admins can call from the browser, or provide a web dashboard for secret management.
Context
Wild Lychee AI admin panel. Community managers (non-technical users) need to enter their API key without using the terminal.