Update systemPrompt and/or dynamicPromptEnabled

curl --request PATCH \
  --url https://api.gennia.ai/public/api/v1/agents/{agentPublicId}/prompt \
  --header 'Content-Type: application/json' \
  --header 'X-Api-Key: <api-key>' \
  --data '
{
  "dynamicPromptEnabled": true,
  "systemPrompt": "You are a friendly support agent for Acme Corp."
}
'

{
  "dynamicPromptEnabled": true,
  "systemPrompt": "<string>",
  "variables": [
    {
      "booleanTextWhenFalse": "<string>",
      "booleanTextWhenTrue": "<string>",
      "createdAt": "2023-11-07T05:31:56Z",
      "defaultValue": {},
      "description": "<string>",
      "label": "<string>",
      "multiChoiceSeparator": "<string>",
      "name": "<string>",
      "options": [
        {
          "injectedText": "<string>",
          "label": "<string>",
          "publicId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
          "sortOrder": 123
        }
      ],
      "publicId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
      "required": true,
      "sortOrder": 123,
      "updatedAt": "2023-11-07T05:31:56Z"
    }
  ]
}