* feat: refactor UI to use coss + coupons UI
* fix: use TRPCError and remove sensitive logging in createCoupon handler
- Replace plain Error with TRPCError for consistent tRPC error handling
- Use INTERNAL_SERVER_ERROR for missing env configuration
- Use UNAUTHORIZED for permission denied errors
- Use BAD_REQUEST for API failure errors
- Remove console.warn that logged username (sensitive info)
Co-Authored-By: unknown <>
* feat: add copy button and fix 0 on % off
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Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>