feat: 전문적이고 모던한 OAuth 로그인 UI 구현

- AiMond Authorization 브랜딩 적용
- 다크모드 기반 글래스모피즘 디자인
- 애니메이션 효과 (플로팅, 그라디언트, 포커스)
- React Router 기반 라우팅 구조
- AuthContext를 통한 인증 상태 관리
- 대시보드 및 관리 페이지 기본 구조
- Backend API 엔드포인트 구조 개선
- pymongo 호환성 문제 수정

🤖 Generated with [Claude Code](https://claude.ai/code)

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

oauth/backend/app/api/v1/endpoints/applications.py

@@ -0,0 +1,37 @@
+from fastapi import APIRouter, Depends, HTTPException
+from typing import List
+from app.core.security import get_current_user
+from app.models.user import User
+from app.models.application import Application
+
+router = APIRouter()
+
+@router.get("/", response_model=List[Application])
+async def get_applications(current_user: User = Depends(get_current_user)):
+    # TODO: Implement application list logic
+    return []
+
+@router.post("/", response_model=Application)
+async def create_application(
+    app_data: dict,
+    current_user: User = Depends(get_current_user)
+):
+    # TODO: Implement application creation logic
+    return {"message": "Application created"}
+
+@router.put("/{app_id}")
+async def update_application(
+    app_id: str,
+    app_data: dict,
+    current_user: User = Depends(get_current_user)
+):
+    # TODO: Implement application update logic
+    return {"message": f"Application {app_id} updated"}
+
+@router.delete("/{app_id}")
+async def delete_application(
+    app_id: str,
+    current_user: User = Depends(get_current_user)
+):
+    # TODO: Implement application deletion logic
+    return {"message": f"Application {app_id} deleted"}