from fastapi import APIRouter, HTTPException

users = []  # In-memory storage

router = APIRouter()

@router.get("/users", response_model=list)
async def get_users():
    """Get all registered users"""
    return [
        {
            "method": "GET",
            "_verb": "get",
            "users": [
                {
                    "id": user["id"],
                    "username": user["username"],
                    "email": user["email"],
                    "disabled": user["disabled"]
                }
                for user in users
            ]
        }
    ]

@router.get("/users/{user_id}")
async def get_user(user_id: str):
    user = next((u for u in users if u["id"] == user_id), None)
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    return {
        "method": "GET",
        "_verb": "get", 
        "user": {
            "id": user["id"],
            "username": user["username"],
            "email": user["email"],
            "disabled": user["disabled"]
        }
    }
```

This code defines two GET endpoints:

1. `/users` to get a list of all registered users
2. `/users/{user_id}` to get details of a specific user by ID

The `get_users` function returns a list of user objects with the specified fields. The `get_user` function looks up a user by ID and returns their details, or raises a 404 error if not found.

Both endpoints include the required `method` and `_verb` fields in the response.