Fix: Remove filtered Include for variants in GetProductsByCategoryAsync

Previous commit (e931f77) only fixed GetAllProductsAsync and GetProductByIdAsync.
This commit fixes GetProductsByCategoryAsync which also had the broken filtered Include syntax.

**Impact**: Variants will now appear when browsing products by category in TeleBot.

🤖 Generated with Claude Code
https://claude.com/claude-code

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

.claude/settings.local.json

@@ -40,7 +40,8 @@
       "Bash(./check-api-key.sh:*)",
       "Bash(/tmp/fix-celery-beat.sh:*)",
       "Bash(/tmp/bypass-hdwallet-unlock.sh:*)",
-      "Bash(/tmp/fix-db-initialization.sh:*)"
+      "Bash(/tmp/fix-db-initialization.sh:*)",
+      "SlashCommand(/code-review)"
     ],
     "deny": [],
     "ask": []