feat: close stub-page gaps - profile login/logout, admin Reports/Settings, Help/Docs links

Sprint A: storefront header profile control (login/logout only, no menu),
wired to existing customer Telegram auth (AuthService).

Sprint B: backoffice/reports page, reuses AdminAnalyticsFacade (Sales,
Top Products, Marketplace Health cards + CSV export).

Sprint C: backoffice/settings page, admin UI density preference
(comfortable/compact), localStorage-persisted, applied to app-table
across all admin list pages.

Sprint D: admin bottom-nav Help -> mailto using existing supportEmail,
Documentation -> external link via new TenantConfig.documentationUrl.
AdminNavLink gains externalHref for non-routerLink nav entries.

Docs: docs/GLOBAL-SPRINT-PLAN.md tracks the full sprint breakdown.
docs/COMING-SOON-AUDIT.md removed, folded into docs/KNOWN-ISSUES.md.
docs/BACKEND.md updated with the new documentationUrl bootstrap field.

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

src/assets/mock/bootstrap/bootstrap.json

@@ -14,7 +14,8 @@
     "supportedLocales": ["ru", "en", "hy"],
     "defaultCurrency": "RUB",
     "supportedCurrencies": ["RUB", "USD", "EUR", "AMD"],
-    "timezone": "Europe/Moscow"
+    "timezone": "Europe/Moscow",
+    "documentationUrl": "https://docs.marketplace.local"
   },
   "branding": {
     "brandName": "Marketplace",