Add SNS Marketing Campaign feature

- Add cash_cc_balance to User model (withdrawable CC)
- Create SnsShareSubmission model for SNS share verification
- Add marketing campaign settings to SystemSettings
- Add reward_type to ReferralReward model
- Create /api/sns-share endpoints for submission and verification
- Add referral signup reward logic (10CC on signup)
- Create /sns-share user page for SNS sharing
- Create /admin/sns-shares management page
- Add marketing settings UI to admin settings page
- Add SNS Shares menu to admin sidebar

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/api/auth.py

@@ -7,7 +7,7 @@ from pydantic import BaseModel
 from typing import Optional
 import bcrypt
 from ..database import get_db
-from ..models import User
+from ..models import User, SystemSettings, ReferralReward
 from ..models.user import generate_referral_code
 from ..schemas import UserCreate, UserUpdate, UserResponse, Token
 from ..config import get_settings
@@ -151,6 +151,32 @@ def register(user_data: UserCreate, db: Session = Depends(get_db)):
     db.add(user)
     db.commit()
     db.refresh(user)
+
+    # 레퍼럴 가입 보상 처리
+    if user.referred_by:
+        # 추천인 찾기
+        referrer = db.query(User).filter(User.referral_code == user.referred_by).first()
+        if referrer:
+            # 설정에서 보상 CC 가져오기
+            sys_settings = db.query(SystemSettings).first()
+            reward_cc = sys_settings.referral_signup_reward_cc if sys_settings else 10.0
+
+            # 추천인에게 CC 지급 (프로모션 CC - 출금 불가)
+            referrer.cc_balance += reward_cc
+
+            # 레퍼럴 보상 기록 생성
+            referral_reward = ReferralReward(
+                referrer_id=referrer.id,
+                referred_user_id=user.id,
+                reward_type="signup",
+                payment_amount=0.0,
+                reward_amount=reward_cc,
+                status="credited",
+                credited_at=datetime.utcnow(),
+            )
+            db.add(referral_reward)
+            db.commit()
+
     return user