feat(rebrand): pricing market-calibrated + remove /fiverr entirely

PRICING (/hytale) calibrated from market research (RESEARCH/Hytale/):
- Plugin Express: from 400€ (1-2j, petit système scopé)
- Projet Sur-Mesure: from 1 500€ (2-6 sem, featured popular)
- Système MMO Complet: from 5 000€ (4-8 sem, stack complet)
- Retainer Mensuel: from 800€/mois (4-8h/sem)
- Site Gaming/Serveur: from 1 000€ (Nuxt SSR + vote-rewards)

Source: TJM défensif senior Java FR 7ans = €450-650/jour (Freelance.com,
Arc.dev, Portage360). Segments cibles : small network (2-5 staff) +
mid-tier RPG/MMO (5-15 staff). Hobbyistes redirigés vers plugins
productisés BBB $15-25 (phase 10 future).

REMOVED /fiverr page entirely:
- Deleted app/pages/fiverr.vue (page removed from build + SEO)
- Removed from AppHeader navLinks + AppFooter quickLinks + socialLinks
- Removed nav.fiverr + a11y.fiverr + seo.fiverr + full fiverr.* block
  from fr.json + en.json (~75 clés chacun)
- Removed fiverr + FiverrConfig + FiverrService from site.ts + shared types
- Removed /fiverr internal links priority (redirected to /hytale)
- JSON-LD index.vue sameAs cleaned (LinkedIn + Gitea only, no Fiverr)
- reviewsLink testimonials redirected to /contact
Rationale: analyse de marché explicite "Fiverr destroys senior
positioning faster than it generates revenue"

RESEARCH/Hytale/ added (3 deep reports on pricing + prospection).

app/components/layout/AppHeader.vue

@@ -12,7 +12,6 @@ const navLinks = computed(() => [
   { key: 'projects', path: '/projects' },
   { key: 'about', path: '/about' },
   { key: 'contact', path: '/contact' },
-  { key: 'fiverr', path: '/fiverr' },
 ])
 
 function toggleLocale() {