feat(economy): creator payout request models, migration, and API

backend/app/models/marketplace.py

@@ -153,3 +153,43 @@ class CreatorBalance(Base):
     )
 
     user = relationship("User", foreign_keys=[user_id])
+
+
+class PayoutStatus(str, enum.Enum):
+    pending = "pending"
+    approved = "approved"
+    paid = "paid"
+    rejected = "rejected"
+
+
+class PayoutRequest(Base):
+    __tablename__ = "payout_requests"
+
+    id = Column(BigInteger, primary_key=True, autoincrement=True)
+    creator_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True)
+    amount = Column(BigInteger, nullable=False)
+    status = Column(
+        Enum(PayoutStatus, name="payout_status"),
+        nullable=False,
+        default=PayoutStatus.pending,
+        server_default=PayoutStatus.pending.value,
+    )
+    external_ref = Column(String(255), nullable=True)
+    provider_ref = Column(String(255), nullable=True)
+    requested_by = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True)
+    reviewed_by = Column(Integer, ForeignKey("users.id", ondelete="SET NULL"), nullable=True, index=True)
+    reviewed_at = Column(DateTime(timezone=True), nullable=True)
+    created_at = Column(
+        DateTime(timezone=True),
+        nullable=False,
+        default=lambda: datetime.now(timezone.utc),
+        server_default=func.now(),
+    )
+
+    __table_args__ = (
+        CheckConstraint("amount > 0", name="check_payout_amount_positive"),
+    )
+
+    creator = relationship("User", foreign_keys=[creator_id])
+    requester = relationship("User", foreign_keys=[requested_by])
+    reviewer = relationship("User", foreign_keys=[reviewed_by])