feat: Add GDPR compliance and improve UI/UX

GDPR Compliance:
- Delete CV files immediately after processing
- Add DataRetentionJob to auto-purge data after 30 days
- Add DeleteAllUserDataAsync for right to erasure
- Add Privacy Policy page with GDPR information
- Add privacy link and GDPR badge to footer

UI/UX Improvements:
- Add "Why Choose RealCV" benefits section to homepage
- Fix pricing page: Professional card highlight, consistent button styles
- Improve text contrast on dark backgrounds (0.75 → 0.85 opacity)
- Fix auth page messaging consistency
- Fix CSS --realcv-accent variable (was self-referencing)

UK Terminology:
- Change "hiring" to "recruitment" throughout
- Change "bad hires" to "poor appointments"

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/RealCV.Application/Interfaces/ICVCheckService.cs

@@ -11,4 +11,9 @@ public interface ICVCheckService
     Task<List<CVCheckDto>> GetUserChecksAsync(Guid userId);
     Task<VeracityReport?> GetReportAsync(Guid checkId, Guid userId);
     Task<bool> DeleteCheckAsync(Guid checkId, Guid userId);
+
+    /// <summary>
+    /// GDPR: Delete all CV checks and associated data for a user (right to erasure).
+    /// </summary>
+    Task<int> DeleteAllUserDataAsync(Guid userId);
 }