enrich workspace table information

app/models/workspace.py

@@ -5,12 +5,19 @@ from .base import AutoID, Base
 class Workspace(Base, AutoID):
     """工作区表"""
     __tablename__ = "workspaces"
-
+    
+    # --- 基础与个性化 ---
     name = Column(String, nullable=False)
+    slug = Column(String, unique=True, index=True, nullable=False)
+    logo = Column(String, nullable=True)
+    description = Column(String, nullable=True)
+
     # 存储容量上限（单位：字节 Bytes），默认 5GB
-    storage_limit = Column(BigInteger, default=5 * 1024 * 1024 * 1024) 
+    storage_limit = Column(BigInteger, default=5 * 1024 * 1024 * 1024)
+    storage_used = Column(BigInteger, default=0, nullable=False)
 
     created_at = Column(DateTime(timezone=True), server_default=func.now())
+    updated_at = Column(DateTime(timezone=True), onupdate=func.now())
 
 
 class WorkspaceMember(Base, AutoID):