i am new to kibana and using vega and am trying to create a meshnet with the espressiff environment and i m sending mqtt msg from my root esp to kibana. i can see the msg in the discover section and they look like this:

enter image description here

this comes from this schema:

enter image description here

so i tried using vega but i m not getting anything
right now the amount of nodes inside my mesh net are 3

how can i visualize this. i havent found anything that really helped me up until now.

this is what i ve tried up until now. and i get the err:

enter image description here

{
  "$schema": "https://vega.github.io/schema/vega/v5.json",
  "description": "A tree diagram showing sensor connections.",
  "data": [
    {
      "name": "edges",
      "url": {
        "%context%": true,
        "index": "25_36_170",  
        "body": {
          "size": 3,
          "_source": ["sensors.values.edges.from", "sensors.values.edges.to"]
        }
      },
      "format": { "property": "hits.hits" }
    },
    {
      "name": "nodes",
      "source": "edges",
      "transform": [
        {
          "type": "flatten",
          "fields": ["_source.sensors.values.edges"]
        },
        {
          "type": "formula",
          "as": "source",
          "expr": "datum['_source.sensors.values.edges'].from"
        },
        {
          "type": "formula",
          "as": "target",
          "expr": "datum['_source.sensors.values.edges'].to"
        },
        {
          "type": "fold",
          "fields": ["source", "target"]
        },
        {
          "type": "identifier",
          "as": "id"
        },
        {
          "type": "formula",
          "as": "node",
          "expr": "datum.value"
        },
        {
          "type": "collect",
          "sort": { "field": "node" }
        }
      ]
    }
  ],
  "scales": [
    {
      "name": "color",
      "type": "ordinal",
      "domain": { "data": "nodes", "field": "node" },
      "range": { "scheme": "category10" }
    }
  ],
  "marks": [
    {
      "type": "text",
      "from": { "data": "nodes" },
      "encode": {
        "enter": {
          "x": { "field": "id", "type": "ordinal", "band": 0.5 },
          "y": { "field": "id", "type": "ordinal", "band": 0.5 },
          "text": { "field": "node" },
          "fill": { "scale": "color", "field": "node" }
        }
      }
    }
  ]
}