Create json-schema for code flow canvas format

[devhelpr]

An example of the current format:

{
  "schemaType": "flow",
  "schemaVersion": "0.0.1",
  "id": "1234",
  "flows": {
    "flow": {
      "flowType": "flow",
      "nodes": [
        {
          "id": "bfc1f21e-5554-46b8-95be-32a8e4ecd3d4",
          "x": 3242.3943267614295,
          "y": 1329.909051146397,
          "width": 200,
          "height": 100,
          "nodeType": "Shape",
          "nodeInfo": {
            "type": "expression",
            "formValues": {
              "expression": "input * 2",
              "inputType": "number"
            },
            "showFormOnlyInPopup": true,
            "isSettingsPopup": true,
            "taskType": "expression"
          }
        },
        {
          "id": "986e849d-3a81-4ab6-a56c-183524d6d270",
          "x": 3442.3943267614295,
          "y": 1379.909051146397,
          "endX": 3614.8220523981977,
          "endY": 1409.9090753896921,
          "startNodeId": "bfc1f21e-5554-46b8-95be-32a8e4ecd3d4",
          "endNodeId": "c649b99d-1e1e-4dc8-92db-b6c9624392fe",
          "startThumbName": "output",
          "endThumbName": "input",
          "lineType": "BezierCubic",
          "nodeType": "Connection",
          "layer": 1,
          "nodeInfo": {}
        },
        {
          "id": "c649b99d-1e1e-4dc8-92db-b6c9624392fe",
          "x": 3614.8220523981977,
          "y": 1379.9090753896921,
          "width": 119.99978198769784,
          "height": 56.00005356426208,
          "nodeType": "Shape",
          "nodeInfo": {
            "type": "show-value",
            "formValues": {
              "append": "",
              "decimals": "0",
              "name": ""
            },
            "initializeOnStartFlow": true,
            "isSettingsPopup": true,
            "taskType": "show-value"
          }
        },
        {
          "id": "7472c6bf-6fec-493b-9a69-07cc1b6bd145",
          "x": 2815.576740104485,
          "y": 1334.6610486961342,
          "width": 245.0001688838781,
          "height": 124.00002793299834,
          "nodeType": "Shape",
          "nodeInfo": {
            "type": "user-input",
            "formValues": {
              "label": "test",
              "value": "",
              "decimals": "2",
              "name": "",
              "group": ""
            },
            "isSettingsPopup": true,
            "isUINode": true,
            "taskType": "user-input"
          }
        },
        {
          "id": "f7a22e9f-6342-4531-9a0f-e71df997d8d7",
          "x": 3060.576908988363,
          "y": 1364.6610486961342,
          "endX": 3242.3943267614295,
          "endY": 1379.909051146397,
          "startNodeId": "7472c6bf-6fec-493b-9a69-07cc1b6bd145",
          "endNodeId": "bfc1f21e-5554-46b8-95be-32a8e4ecd3d4",
          "startThumbName": "output",
          "endThumbName": "input",
          "lineType": "BezierCubic",
          "nodeType": "Connection",
          "layer": 1,
          "nodeInfo": {}
        }
      ]
    }
  },
  "compositions": {}
}

Format should also be improved where possible.