feat(auth): M2 phone_rebind_log 换绑台账模型 + 配置 + 迁移

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

app/models/__init__.py

@@ -32,6 +32,7 @@ from app.models.invite_fingerprint import InviteFingerprint  # noqa: F401
 from app.models.launch_confirm_sample import LaunchConfirmSample  # noqa: F401
 from app.models.meituan_coupon import MeituanCoupon  # noqa: F401
 from app.models.onboarding import OnboardingCompletion  # noqa: F401
+from app.models.phone_rebind_log import PhoneRebindLog  # noqa: F401
 from app.models.ops_marquee_seed import OpsMarqueeSeed  # noqa: F401
 from app.models.ops_stat_config import OpsStatConfig  # noqa: F401
 from app.models.price_observation import PriceObservation  # noqa: F401

app/models/phone_rebind_log.py

@@ -0,0 +1,31 @@
+"""手机号换绑台账。
+
+记录"手机号从老账号被夺走、重建为新账号(X 注销 → Y)"这一破坏性事件,支撑"一个手机号
+30 天内最多换绑一次"的限制。手机号级、渠道无关(source 标来源);普通微信绑定不写此表。
+见 M2 spec §4.1。
+"""
+from __future__ import annotations
+
+from datetime import datetime
+
+from sqlalchemy import DateTime, Integer, String, func
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.db.base import Base
+
+
+class PhoneRebindLog(Base):
+    __tablename__ = "phone_rebind_log"
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    # 被换绑的真实手机号(注意:存真实号,不是老账号被腾号后的 deleted_<id>)
+    phone: Mapped[str] = mapped_column(String(20), index=True, nullable=False)
+    # 被注销的老账号 X;P 换绑时已被腾空(极边界)则为空
+    old_user_id: Mapped[int | None] = mapped_column(Integer, nullable=True)
+    # 换绑后新建的账号 Y
+    new_user_id: Mapped[int] = mapped_column(Integer, nullable=False)
+    # 换绑来源。手机号级配额、渠道无关,留字段给未来其他换绑路径共用同一份 30 天限制。
+    source: Mapped[str] = mapped_column(String(32), nullable=False, default="wechat_conflict")
+    rebound_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), server_default=func.now(), index=True, nullable=False
+    )