Refactor hardcoded URLs to use BASE_URL variable

[coderabbitai]

In the interest of improving code maintainability, it's recommended to update all hardcoded URLs related to WoW marketshare to use the variable. This change should be applied across various files to ensure consistency.

Affected files:

• app/routes/wow.marketshare.recommended.tsx
• app/routes/wow.marketshare._index.tsx
• app/routes/wow._index.tsx
• app/routes/blog.wow.tldr.tsx
• app/routes/blog.wow.crossrealm1.tsx
• app/routes/[sitemap.xml].tsx
• app/routes/_public._index.tsx
• app/components/navigation/sidebar/Sidebar.tsx

Please ensure that all references to WoW marketshare URLs are refactored to use the centralized variable.