Complete backend infrastructure and authentication system

Co-authored-by: mblanke <9078342+mblanke@users.noreply.github.com>

backend/app/schemas/user.py

@@ -0,0 +1,33 @@
+from pydantic import BaseModel
+from typing import Optional
+from datetime import datetime
+
+
+class UserBase(BaseModel):
+    """Base user schema"""
+    username: str
+    role: str = "user"
+    tenant_id: int
+
+
+class UserCreate(UserBase):
+    """Schema for creating a user"""
+    password: str
+
+
+class UserUpdate(BaseModel):
+    """Schema for updating a user"""
+    username: Optional[str] = None
+    password: Optional[str] = None
+    role: Optional[str] = None
+    is_active: Optional[bool] = None
+
+
+class UserRead(UserBase):
+    """Schema for reading user data (excludes password_hash)"""
+    id: int
+    is_active: bool
+    created_at: datetime
+
+    class Config:
+        from_attributes = True