namespaced systems should default to namespace config

[alvrs]

If a project is in multi-namespace mode, and has systems in a directory root, the directory name becomes the default namespace, even if the namespace is defined in the config with an explicit namespace override. I would expect the config namespace override to become the system's namespace, while the directory name is used as the namespace label (and is used to find the corresponding namespace in the config).

Example:

import { defineWorld } from "@latticexyz/world";

export default defineWorld({
  namespaces: {
    root: {
      namespace: "",
      tables: {
        Position: {
          schema: {
            user: "address",
            x: "uint256",
            y: "uint256",
          },
          key: ["user"],
        },
      },
    },
  },
});

src
└── namespaces
    └── root
        └── systems
            └── MoveSystem.sol

Results in

{
  "systems": [
    {
      "namespaceLabel": "root",
      "label": "MoveSystem",
      "namespace": "root",
      "name": "MoveSystem",
      "systemId": "0x7379726f6f740000000000000000000041646d696e53797374656d0000000000",
      "abi": [
        "function move(uint256 x, uint256 y)"
      ],
      "worldAbi": [
        "function root__move(uint256 x, uint256 y)"
      ]
    }
  ]
}

But I would expect
Results in

{
  "systems": [
    {
      "namespaceLabel": "root",
      "label": "MoveSystem",
      "namespace": "",
      "name": "MoveSystem",
      "systemId": "0x7379726f6f740000000000000000000041646d696e53797374656d0000000000",
      "abi": [
        "function move(uint256 x, uint256 y)"
      ],
      "worldAbi": [
        "function move(uint256 x, uint256 y)"
      ]
    }
  ]
}