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/auth.py

@@ -0,0 +1,38 @@
+from fastapi import APIRouter, HTTPException, Depends, status
+from fastapi.security import OAuth2PasswordRequestForm
+from app.core.security import create_access_token, get_current_user
+from app.models.user import User
+from app.core.config import settings
+
+router = APIRouter()
+
+@router.post("/login")
+async def login(form_data: OAuth2PasswordRequestForm = Depends()):
+    # TODO: Implement actual authentication
+    return {
+        "access_token": create_access_token({"sub": form_data.username}),
+        "token_type": "bearer"
+    }
+
+@router.post("/logout")
+async def logout(current_user: User = Depends(get_current_user)):
+    # TODO: Implement logout logic
+    return {"message": "Logged out successfully"}
+
+@router.post("/refresh")
+async def refresh_token(current_user: User = Depends(get_current_user)):
+    # TODO: Implement token refresh logic
+    return {
+        "access_token": create_access_token({"sub": current_user.email}),
+        "token_type": "bearer"
+    }
+
+@router.get("/authorize")
+async def authorize():
+    # TODO: Implement OAuth authorization
+    return {"message": "Authorization endpoint"}
+
+@router.post("/token")
+async def token():
+    # TODO: Implement OAuth token endpoint
+    return {"message": "Token endpoint"}