feat: Phase 9 frontend - Marketplaces registry + Domains & Releases (combined page)

core/marketplace-registry (Marketplace/MarketplaceDomain/
LifecycleAdvanceResult models + gateway/token) derives a single-row
registry from the current tenant's own live bootstrap config and current
hostname, since the platform runs one tenant per deployment today with no
registry anywhere. New features/admin/marketplaces page + nav entry.
Against docs/backend/PHASE-9-TENANT-REGISTRY-DOMAINS-CONTRACT.md.

Scope simplification: combined "Marketplaces" and "Domains & Releases"
(two separate backoffice sections in the plan) into one page with two
sections, to keep pace through this push - splitting them into dedicated
routes is a small follow-up once there's real multi-marketplace data to
justify two separate list views. Onboarding wizard (8 steps), Hostinger
DNS automation, and the full lifecycle-advance state machine are not
built - registry/domain/lifecycle read-only display only.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/i18n/en.ts

@@ -2062,6 +2062,7 @@ export const en: Translations = {
       notifications: 'Notifications',
       integrations: 'Integrations',
       finance: 'Payments & Finance',
+      marketplaces: 'Marketplaces',
       reviews: 'Reviews',
       reports: 'Reports',
       partnersGroup: 'Partners',

src/app/i18n/hy.ts

@@ -2056,6 +2056,7 @@ export const hy: Translations = {
       notifications: 'Ծանուցումներ',
       integrations: 'Ինտեգրումներ',
       finance: 'Վճարումներ և ֆինանսներ',
+      marketplaces: 'Մարկետփլեյսներ',
       transactions: 'Գործարքներ',
       reviews: 'Կարծիքներ',
       reports: 'Հաշվետվություններ',

src/app/i18n/ru.ts

@@ -2056,6 +2056,7 @@ export const ru: Translations = {
       notifications: 'Уведомления',
       integrations: 'Интеграции',
       finance: 'Платежи и финансы',
+      marketplaces: 'Маркетплейсы',
       transactions: 'Транзакции',
       reviews: 'Отзывы',
       reports: 'Отчёты',

src/app/i18n/translations.ts

@@ -2071,6 +2071,7 @@ export interface Translations {
       notifications: string;
       integrations: string;
       finance: string;
+      marketplaces: string;
       reports: string;
       partnersGroup: string;
       sellerManagement: string;