WIP checkpoint: Trust & Safety: Moderation data model + Alembic migration

backend/app/models/appeal.py

@@ -0,0 +1,34 @@
+"""Appeal model for moderation actions."""
+
+from sqlalchemy import Column, Integer, String, Text, DateTime, ForeignKey, Enum
+from sqlalchemy.orm import relationship
+from sqlalchemy.sql import func
+
+from app.database import Base
+
+
+class Appeal(Base):
+    __tablename__ = "appeals"
+
+    id = Column(Integer, primary_key=True)
+    moderation_action_id = Column(
+        Integer, ForeignKey("moderation_actions.id"), nullable=False
+    )
+    user_id = Column(Integer, ForeignKey("users.id"), nullable=False)
+    reason = Column(Text, nullable=False)
+    status = Column(
+        Enum(
+            "pending", "approved", "rejected",
+            name="appeal_status_enum",
+        ),
+        default="pending",
+        nullable=False,
+    )
+    reviewed_by = Column(Integer, ForeignKey("users.id"), nullable=True)
+    reviewed_at = Column(DateTime(timezone=True), nullable=True)
+    created_at = Column(DateTime(timezone=True), server_default=func.now())
+
+    # Relationships
+    moderation_action = relationship("ModerationAction", back_populates="appeals")
+    user = relationship("User", back_populates="appeals")
+    reviewer = relationship("User", foreign_keys=[reviewed_by])