feat(3c): DT 단말 + 콘솔 센터(DC1/DC2/DC3) 전환

- DT 단말(:5180, dt.html/src/dt): 접속 센터 선택 후 해당 Gucci 관문으로 로그인·이체·조회.
  vite.dt.config 프록시 /dc1|/dc2|/dc3 -> 8095|8195|8295. X-Timestamp 초 단위(ReplayGuard).
- 콘솔 센터 전환: auth.ts getDc/setDc + X-RTGS-DC 헤더, App.tsx 드롭다운(+reload),
  vite.config router로 헤더 기반 포트 라우팅(+0/+100/+200) → 3센터 원장·대사·보고서 전환 조회.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/vite.config.ts

@@ -1,22 +1,31 @@
 import { defineConfig } from 'vite'
 import react from '@vitejs/plugin-react'
 
-// RTGS 조회 콘솔 (:5174). Chanel(:8091)로 프록시하여 CORS 회피.
+// RTGS 조회/관리 콘솔 (:5174). 요청 헤더 X-RTGS-DC(DC1/DC2/DC3)로 대상 센터 포트를 라우팅한다.
+//   Chanel계열 8091 / LouisVuitton(admin) 8099 / Gucci 8095, 센터별 +100/+200 오프셋.
+const OFFSET: Record<string, number> = { DC1: 0, DC2: 100, DC3: 200 }
+const off = (req: any) => OFFSET[(req.headers?.['x-rtgs-dc'] as string) || 'DC1'] ?? 0
+const routed = (basePort: number) => ({
+  target: `http://localhost:${basePort}`,
+  changeOrigin: true,
+  router: (req: any) => `http://localhost:${basePort + off(req)}`,
+})
+
 export default defineConfig({
   plugins: [react()],
   server: {
     port: 5174,
     proxy: {
-      '/accounts': { target: 'http://localhost:8091', changeOrigin: true },
-      '/inquiry': { target: 'http://localhost:8091', changeOrigin: true },
-      '/pay': { target: 'http://localhost:8091', changeOrigin: true },
-      '/meta': { target: 'http://localhost:8091', changeOrigin: true },
-      '/rawmessage': { target: 'http://localhost:8091', changeOrigin: true },
-      '/notifications': { target: 'http://localhost:8091', changeOrigin: true },
-      '/ledger': { target: 'http://localhost:8091', changeOrigin: true },
-      '/admin': { target: 'http://localhost:8099', changeOrigin: true },
-      '/console': { target: 'http://localhost:8099', changeOrigin: true },
-      '/gucci': { target: 'http://localhost:8095', changeOrigin: true },
+      '/accounts': routed(8091),
+      '/inquiry': routed(8091),
+      '/pay': routed(8091),
+      '/meta': routed(8091),
+      '/rawmessage': routed(8091),
+      '/notifications': routed(8091),
+      '/ledger': routed(8091),
+      '/admin': routed(8099),
+      '/console': routed(8099),
+      '/gucci': routed(8095),
     },
   },
 })