Refactor-State-Update-Helper

The model receives the prompt (and optional system message). The run uses scorer rubric_json_metrics with the JSON configuration below. Pass/fail and partial credit are determined entirely by that scorer against the model output; no human grading.

Return JSON only with keys plan, refactor, tests. A reducer repeats object spread updates for loading, success, and failure states across three actions. Refactor to a helper without hiding state transitions.

{
  "metrics": {
    "intent": {
      "checks": [
        {
          "contains": [
            "reducer"
          ]
        },
        {
          "contains": [
            "object spread"
          ]
        },
        {
          "contains": [
            "helper"
          ]
        }
      ]
    },
    "visible": {
      "checks": [
        {
          "contains": [
            "loading"
          ]
        },
        {
          "contains": [
            "success"
          ]
        },
        {
          "contains": [
            "failure"
          ]
        }
      ]
    },
    "hidden": {
      "checks": [
        {
          "contains": [
            "state transitions"
          ]
        },
        {
          "contains": [
            "tests"
          ]
        },
        {
          "contains": [
            "immutability"
          ]
        }
      ]
    }
  }
}