fix: improve platform homepage pricing UI and restore footer links

- Fix toggle button alignment with consistent min-widths
- Add € currency signs to all prices
- Show all tier features with greyed unavailable ones
- Add multi-channel integration feature for Enterprise tier
- Change Contact Sales to mailto link (fixes 404)
- Restore footer CMS page links (About, FAQ, Contact)
- Add footer link translations for all 4 languages

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

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

static/locales/en.json

@@ -512,6 +512,7 @@
       "eu_vat_invoicing": "EU VAT invoicing",
       "analytics_dashboard": "Analytics dashboard",
       "api_access": "API access",
+      "multi_channel": "Multi-channel integration",
       "products": "products",
       "team_member": "team member",
       "unlimited": "Unlimited",
@@ -631,7 +632,10 @@
       "contact": "Contact",
       "copyright": "© {year} Wizamart. Built for Luxembourg e-commerce.",
       "privacy": "Privacy Policy",
-      "terms": "Terms of Service"
+      "terms": "Terms of Service",
+      "about": "About Us",
+      "faq": "FAQ",
+      "contact_us": "Contact Us"
     },
     "modern": {
       "badge_integration": "Official Integration",