feat: Add base project structure with API and web components

api/app/models/user_model.py

@@ -0,0 +1,30 @@
+import datetime
+import uuid
+from sqlalchemy import Column, String, Boolean, DateTime, ForeignKey
+from sqlalchemy.dialects.postgresql import UUID
+from sqlalchemy.orm import relationship
+from app.db import Base
+
+class User(Base):
+    __tablename__ = "users"
+
+    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4, index=True)
+    username = Column(String, unique=True, index=True, nullable=False)
+    email = Column(String, unique=True, index=True, nullable=False)
+    hashed_password = Column(String, nullable=False)
+    is_active = Column(Boolean, default=True, nullable=False)
+    is_superuser = Column(Boolean, default=False, nullable=False)
+    created_at = Column(DateTime, default=datetime.datetime.now)
+    updated_at = Column(DateTime, default=datetime.datetime.now, onupdate=datetime.datetime.now)
+    last_login_at = Column(DateTime, nullable=True)  # 最后登录时间，可为空
+    
+    current_workspace_id = Column(UUID(as_uuid=True), ForeignKey("workspaces.id"), nullable=True)  # 当前工作空间ID，可为空
+    
+    # Foreign key to tenant - each user belongs to exactly one tenant
+    tenant_id = Column(UUID(as_uuid=True), ForeignKey("tenants.id"), nullable=False)
+    
+    # Relationship to workspace memberships - users collaborate in workspaces through membership
+    workspaces = relationship("WorkspaceMember", back_populates="user")
+    
+    # Relationship to tenant - one-to-one relationship
+    tenant = relationship("Tenants", back_populates="users")