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.Web/appsettings.json

@@ -3,6 +3,9 @@
     "DefaultConnection": "Server=.;Database=RealCV;Trusted_Connection=True;TrustServerCertificate=True;",
     "HangfireConnection": "Server=.;Database=RealCV_Hangfire;Trusted_Connection=True;TrustServerCertificate=True;"
   },
+  "DataRetention": {
+    "CVCheckRetentionDays": 30
+  },
   "CompaniesHouse": {
     "BaseUrl": "https://api.company-information.service.gov.uk",
     "ApiKey": ""