refactor(core): keep plan prices, cloud quotas and public URLs in one contract (WS-A)

Prices, quotas and site URLs were copied by hand into the edge functions,
admin, desktop and the landing site, and the copies disagreed (Payple billed
9,900/29,900 KRW, admin labels said 12,900/24,900 KRW and $9.9/$19.9, the
site said 2,900/8,900 KRW).

- packages/core/src/plan-catalog.ts is the single source for PLAN_PRICE_KRW
  (Free 0 / Pro 2,900 / Pro+ 8,900 a month) and PLAN_QUOTA.
- packages/core/src/web-urls.ts is the single source for the public origin,
  the /app web-app base path, SITE_URLS and billingUrl().
- Deno cannot bundle packages/core, so scripts/ci/sync-core-contract.mjs
  generates _shared/core-contract.generated.ts; `npm run contract:check`
  fails on drift (same pattern as version:sync).
- Payple checkout, renewal and webhook amount checks now bill the catalog
  price, so existing subscribers move to the new price at their next renewal.
  quota.ts, team-contract.ts and the tests read the generated values.
- Admin MRR/ARR is computed in KRW from the catalog; license labels, the
  release link and desktop PREMIUM_LLM limits derive from core; the site
  imports prices and quotas directly.

Policy: docs/REFACTOR_POLICY.md Wave 3, W3-1 and W3-2.

apps/admin/src/lib/subscription-metrics.ts

@@ -1,17 +1,12 @@
 import 'server-only'
 
+import { PLAN_PRICE_KRW } from '@d3ro/core/plan-catalog'
 import { getSupabaseAdminClient } from './supabase-admin'
 
-/** Monthly list price per tier, in USD. */
-const TIER_MONTHLY_USD: Record<'pro' | 'pro_plus' | 'free', number> = {
-  pro: 9.9,
-  pro_plus: 19.9,
-  free: 0,
-}
-
 export interface SubscriptionRevenue {
-  mrrUsd: number
-  arrUsd: number
+  /** Monthly list-price revenue in KRW (PLAN_PRICE_KRW; provider currency is not tracked per row). */
+  mrrKrw: number
+  arrKrw: number
   activeCount: number
   tierBreakdown: { pro: number; pro_plus: number; free: number }
 }
@@ -19,7 +14,7 @@ export interface SubscriptionRevenue {
 /**
  * Aggregates real subscription revenue from Supabase.
  * Only status === 'active' subscriptions contribute to MRR/ARR.
- * MRR = Σ(monthly price of each active subscription's tier); ARR = MRR * 12.
+ * MRR = Σ(PLAN_PRICE_KRW of each active subscription's tier); ARR = MRR * 12.
  */
 export async function fetchSubscriptionRevenue(): Promise<SubscriptionRevenue> {
   const supabase = await getSupabaseAdminClient('manager')
@@ -37,7 +32,7 @@ export async function fetchSubscriptionRevenue(): Promise<SubscriptionRevenue> {
   }
 
   const tierBreakdown = { pro: 0, pro_plus: 0, free: 0 }
-  let mrrUsd = 0
+  let mrrKrw = 0
   let activeCount = 0
 
   for (const row of rows) {
@@ -46,12 +41,9 @@ export async function fetchSubscriptionRevenue(): Promise<SubscriptionRevenue> {
     const tier = row.tier
     if (tier === 'pro' || tier === 'pro_plus' || tier === 'free') {
       tierBreakdown[tier] += 1
-      mrrUsd += TIER_MONTHLY_USD[tier]
+      mrrKrw += PLAN_PRICE_KRW[tier]
     }
   }
 
-  mrrUsd = Math.round(mrrUsd * 100) / 100
-  const arrUsd = Math.round(mrrUsd * 12 * 100) / 100
-
-  return { mrrUsd, arrUsd, activeCount, tierBreakdown }
+  return { mrrKrw, arrKrw: mrrKrw * 12, activeCount, tierBreakdown }
 }