docs: Mark Product Search as completed in MVP progress

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: KoderFPV

README.md

@@ -94,7 +94,7 @@ Project in initialization phase.
 | Feature | Status |
 |---------|--------|
 | Login | ✅ |
-| Product Search | ❌ |
+| Product Search | ✅ |
 | Checkout | ❌ |
 | Payments | ❌ |
 | Add New Products | ✅ |