Spec C §3.6/§6.2. Бэкенд: GET /api/billing/balance-status (frozen + capacity + required + дефицит ₽/leads), Pest 6. Фронт: BalanceFrozenBanner (в AppLayout, глобально), BalanceCapacityIndicator (в BillingView под балансом), ProjectLimitOverloadDialog (409-перехват в NewProjectDialog: save-blocked/set-zero), tenantStore + api getBalanceStatus. Vitest +18.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
api/billing.ts (getWallet) + BillingView тянет GET /api/billing/wallet
на mount (шапка + BalanceCard, loading/error-state). BalanceCard на
реальные props с nullable-тарифом. featureLabel для feature-слагов.
Sprint 2 Plan C, audit E3 (frontend pt1).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>