feat: 平台规则从硬编码改为品牌方上传文档 + AI 解析

- 新增 PlatformRule 模型 (draft/active/inactive 状态流转)
- 新增文档解析服务 (PDF/Word/Excel → 纯文本)
- 新增 4 个 API: 解析/确认/查询/删除平台规则
- 脚本审核优先从 DB 读取 active 规则，硬编码兜底
- 视频审核合并平台规则违禁词到检测列表
- Alembic 迁移 006: platform_rules 表

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/app/models/__init__.py

@@ -10,7 +10,7 @@ from app.models.task import Task, TaskStage, TaskStatus
 from app.models.brief import Brief
 from app.models.ai_config import AIConfig
 from app.models.review import ReviewTask, Platform
-from app.models.rule import ForbiddenWord, WhitelistItem, Competitor
+from app.models.rule import ForbiddenWord, WhitelistItem, Competitor, PlatformRule, RuleStatus
 from app.models.audit_log import AuditLog
 from app.models.message import Message
 # 保留 Tenant 兼容旧代码，但新代码应使用 Brand
@@ -44,6 +44,8 @@ __all__ = [
     "ForbiddenWord",
     "WhitelistItem",
     "Competitor",
+    "PlatformRule",
+    "RuleStatus",
     # 审计日志
     "AuditLog",
     # 消息

backend/app/models/rule.py

@@ -1,7 +1,8 @@
 """
 规则模型
-违禁词、白名单、竞品
+违禁词、白名单、竞品、平台规则
 """
+import enum
 from typing import TYPE_CHECKING, Optional
 from sqlalchemy import String, Text, ForeignKey
 from app.models.types import JSONType
@@ -13,6 +14,13 @@ if TYPE_CHECKING:
     from app.models.tenant import Tenant
 
 
+class RuleStatus(str, enum.Enum):
+    """平台规则状态"""
+    DRAFT = "draft"        # AI 解析完成，待确认
+    ACTIVE = "active"      # 品牌方已确认，生效中
+    INACTIVE = "inactive"  # 已停用
+
+
 class ForbiddenWord(Base, TimestampMixin):
     """违禁词表"""
     __tablename__ = "forbidden_words"
@@ -83,3 +91,36 @@ class Competitor(Base, TimestampMixin):
 
     def __repr__(self) -> str:
         return f"<Competitor(name={self.name}, brand_id={self.brand_id})>"
+
+
+class PlatformRule(Base, TimestampMixin):
+    """平台规则表 — 品牌方上传文档 + AI 解析"""
+    __tablename__ = "platform_rules"
+
+    id: Mapped[str] = mapped_column(String(64), primary_key=True)
+    tenant_id: Mapped[str] = mapped_column(
+        String(64),
+        ForeignKey("tenants.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
+    brand_id: Mapped[str] = mapped_column(String(64), nullable=False, index=True)
+    platform: Mapped[str] = mapped_column(String(50), nullable=False, index=True)
+
+    # 文档信息
+    document_url: Mapped[str] = mapped_column(String(2048), nullable=False)
+    document_name: Mapped[str] = mapped_column(String(512), nullable=False)
+
+    # AI 解析结果（JSON）
+    parsed_rules: Mapped[Optional[dict]] = mapped_column(JSONType, nullable=True)
+
+    # 状态
+    status: Mapped[str] = mapped_column(
+        String(20), nullable=False, default=RuleStatus.DRAFT.value, index=True,
+    )
+
+    # 关联
+    tenant: Mapped["Tenant"] = relationship("Tenant", back_populates="platform_rules")
+
+    def __repr__(self) -> str:
+        return f"<PlatformRule(id={self.id}, platform={self.platform}, status={self.status})>"

backend/app/models/tenant.py

@@ -10,7 +10,7 @@ from app.models.base import Base, TimestampMixin
 if TYPE_CHECKING:
     from app.models.ai_config import AIConfig
     from app.models.review import ReviewTask
-    from app.models.rule import ForbiddenWord, WhitelistItem, Competitor
+    from app.models.rule import ForbiddenWord, WhitelistItem, Competitor, PlatformRule
 
 
 class Tenant(Base, TimestampMixin):
@@ -48,5 +48,11 @@ class Tenant(Base, TimestampMixin):
         back_populates="tenant",
         lazy="selectin",
     )
+    platform_rules: Mapped[list["PlatformRule"]] = relationship(
+        "PlatformRule",
+        back_populates="tenant",
+        lazy="selectin",
+    )
+
     def __repr__(self) -> str:
         return f"<Tenant(id={self.id}, name={self.name})>"