System updates

✨ New Features
🖼️ Image Attachments for Reward Tiers
Business owners can now attach a strip image to each reward tier on Reward loyalty cards. When customers view their card, the available rewards are displayed with a visual image — making the card more engaging and rewards easier to recognize.
🐛 Bug Fixes
🎨 Stamp Card Icon Positioning
Fixed a bug where the custom inactive stamp icon shifted to the bottom-right corner when the card was added to a wallet, despite rendering correctly in the admin preview.
🔌 Stripe Credentials Validation
Resolved an issue where Stripe appeared disconnected in the admin panel even after a client successfully connected it, preventing sub-accounts from making payments. Stripe credential validation is now more robust.