Add multi-tenant architecture and advanced document parsing capabilities

app/models/user.py

@@ -4,8 +4,9 @@ User model for authentication and user management.
 
 from datetime import datetime
 from typing import Optional
-from sqlalchemy import Column, String, DateTime, Boolean, Text, Enum
+from sqlalchemy import Column, String, DateTime, Boolean, Text, Enum, ForeignKey
 from sqlalchemy.dialects.postgresql import UUID
+from sqlalchemy.orm import relationship
 import uuid
 import enum
 
@@ -58,6 +59,9 @@ class User(Base):
     oauth_provider = Column(String(50), nullable=True)  # auth0, cognito, etc.
     oauth_id = Column(String(255), nullable=True)
     
+    # Tenant relationship
+    tenant_id = Column(UUID(as_uuid=True), ForeignKey("tenants.id"), nullable=False)
+    
     # Timestamps
     created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
     updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
@@ -68,6 +72,9 @@ class User(Base):
     language = Column(String(10), default="en")
     notification_preferences = Column(Text, nullable=True)  # JSON string
     
+    # Relationships
+    tenant = relationship("Tenant", back_populates="users")
+    
     def __repr__(self) -> str:
         return f"<User(id={self.id}, email='{self.email}', role='{self.role}')>"