feat(auth-adapter,bff-kit,client-shell): 마지막 추출 배치

@yakcloud/auth-adapter: core 인터페이스(프레임워크 무관, ds-sdk type-only)
  + dev-bypass + next-auth 격리 계층(peer). exports 서브패스(./core·./dev-bypass).
@yakcloud/bff-kit: respond(web 표준)·serialize(Prisma-free)·ratelimit·session(AuthAdapter DI).
  auth-adapter=devDependency(type-only), 죽은 next peer 제거.
@yakcloud/client-shell: ServiceClientShell 셸 크롬(헤더/탭/pane/가드)+패널 슬롯+BackupPanel 스텁.
  (FileBrowser 는 Phase 1)

FIX-FIRST 반영: client-shell tsconfig jsx:react-jsx + @types/react(-dom),
  bff-kit/auth-adapter += @types/node. 7개 패키지 전부 tsc --noEmit 통과.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/bff-kit/package.json

@@ -26,10 +26,10 @@
   },
   "dependencies": {
     "zod": "^4.4.3",
-    "@yakcloud/ds-sdk": "workspace:*",
-    "@yakcloud/auth-adapter": "workspace:*"
+    "@yakcloud/ds-sdk": "workspace:*"
   },
-  "peerDependencies": {
-    "next": ">=15"
+  "devDependencies": {
+    "@types/node": "^20",
+    "@yakcloud/auth-adapter": "workspace:*"
   }
 }