fix: field schema map paths

[jacobsfletch]

Continuation of #10638. Field paths within the schema map are not correct.

For example, an unnamed tab containing a text field should have the schema path:

• _index-0.fieldWithinUnnamedTab

However, within the schema map that path is formatted as:

• fieldWithinUnnamedTab

The leading index in the first example should exist, as this field is nested within another field, regardless of this field being unnamed. Otherwise, it would be impossible to traverse the schema and lookup this field. This discrepancy does not present itself easily, though, because fields are also provided the wrong schema paths. They can properly locate their schema within the schema map because they match despite being incorrect.

Here's comprehensive example of how field paths should be formatted:

{
  // ...
  fields: [
    {
      // path: 'topLevelNamedField'
      // schemaPath: 'topLevelNamedField'
      // indexPath: ''
      name: 'topLevelNamedField',
      type: 'text',
    },
    {
      // path: 'array'
      // schemaPath: 'array'
      // indexPath: ''
      name: 'array',
      type: 'array',
      fields: [
        {
          // path: 'array.[n].fieldWithinArray'
          // schemaPath: 'array.fieldWithinArray'
          // indexPath: ''
          name: 'fieldWithinArray',
          type: 'text',
        },
        {
          // path: 'array.[n].nestedArray'
          // schemaPath: 'array.nestedArray'
          // indexPath: ''
          name: 'nestedArray',
          type: 'array',
          fields: [
            {
              // path: 'array.[n].nestedArray.[n].fieldWithinNestedArray'
              // schemaPath: 'array.nestedArray.fieldWithinNestedArray'
              // indexPath: ''
              name: 'fieldWithinNestedArray',
              type: 'text',
            },
          ],
        },
        {
          // path: 'array.[n]._index-2'
          // schemaPath: 'array._index-2'
          // indexPath: '2'
          type: 'row',
          fields: [
            {
              // path: 'array.[n].fieldWithinRowWithinArray'
              // schemaPath: 'array._index-2.fieldWithinRowWithinArray'
              // indexPath: ''
              name: 'fieldWithinRowWithinArray',
              type: 'text',
            },
          ],
        },
      ],
    },
    {
      // path: '_index-2'
      // schemaPath: '_index-2'
      // indexPath: '2'
      type: 'row',
      fields: [
        {
          // path: 'fieldWithinRow'
          // schemaPath: '_index-2.fieldWithinRow'
          // indexPath: ''
          name: 'fieldWithinRow',
          type: 'text',
        },
      ],
    },
    {
      // path: '_index-3'
      // schemaPath: '_index-3'
      // indexPath: '3'
      type: 'tabs',
      tabs: [
        {
          // path: '_index-3-0'
          // schemaPath: '_index-3-0'
          // indexPath: '3-0'
          label: 'Unnamed Tab',
          fields: [
            {
              // path: 'fieldWithinUnnamedTab'
              // schemaPath: '_index-3-0.fieldWithinUnnamedTab'
              // indexPath: ''
              name: 'fieldWithinUnnamedTab',
              type: 'text',
            },
            {
              // path: '_index-3-0-1'
              // schemaPath: '_index-3-0-1'
              // indexPath: '3-0-1'
              type: 'tabs',
              tabs: [
                {
                  // path: '_index-3-0-1-0'
                  // schemaPath: '_index-3-0-1-0'
                  // indexPath: '3-0-1-0'
                  label: 'Nested Unnamed Tab',
                  fields: [
                    {
                      // path: 'fieldWithinNestedUnnamedTab'
                      // schemaPath: '_index-3-0-1-0.fieldWithinNestedUnnamedTab'
                      // indexPath: ''
                      name: 'fieldWithinNestedUnnamedTab',
                      type: 'text',
                    },
                  ],
                },
              ],
            },
          ],
        },
        {
          // path: 'namedTab'
          // schemaPath: '_index-3.namedTab'
          // indexPath: ''
          label: 'Named Tab',
          name: 'namedTab',
          fields: [
            {
              // path: 'namedTab.fieldWithinNamedTab'
              // schemaPath: '_index-3.namedTab.fieldWithinNamedTab'
              // indexPath: ''
              name: 'fieldWithinNamedTab',
              type: 'text',
            },
          ],
        },
      ],
    },
  ]
}