Reward System Overhaul & Bug Fix

Reward System Overhaul & Bug Fix

This iteration focuses on fixing a critical bug while fundamentally improving the player's experience when claiming rewards.

### ✅ Feature Checklist

#### Rewards & Quality of Life

- [x] **Persistent Rewards Fix:** Fixed a critical bug where unclaimed rewards from the Exotic Trader would be lost if the player switched views. Reward state is now persistent and safely stored until claimed.

- [x] **Always-Visible Claim UI:** The reward claim UI has been moved from the Exotic Trader's view to the main Inventory panel. This ensures the player always sees a prominent notification for pending rewards, allowing them to be claimed anytime, anywhere.