Initial commit: Backend API Phase 1a complete

- FastAPI backend with JWT auth
- PostgreSQL database schema
- Trees and Sessions CRUD APIs
- Export functionality (Markdown, Text, HTML)
- Docker setup for local development
- Alembic migrations

backend/app/schemas/user.py

@@ -0,0 +1,34 @@
+from datetime import datetime
+from typing import Optional
+from uuid import UUID
+from pydantic import BaseModel, EmailStr, Field
+
+
+class UserBase(BaseModel):
+    email: EmailStr
+    name: str = Field(..., min_length=1, max_length=255)
+
+
+class UserCreate(UserBase):
+    password: str = Field(..., min_length=10, description="Password must be at least 10 characters")
+
+
+class UserUpdate(BaseModel):
+    name: Optional[str] = Field(None, min_length=1, max_length=255)
+    email: Optional[EmailStr] = None
+
+
+class UserLogin(BaseModel):
+    email: EmailStr
+    password: str
+
+
+class UserResponse(UserBase):
+    id: UUID
+    role: str
+    team_id: Optional[UUID] = None
+    created_at: datetime
+    last_login: Optional[datetime] = None
+
+    class Config:
+        from_attributes = True