How to get display value of multi select custom field

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7

For your example that would look like:

stream: {
    $id: "location-stream",
    filter: {
      savedFilterIds: ["xxx"],
    },
    fields: [ "id", "name", "slug", "c_options" ],
    transform: {
      replaceOptionValuesWithDisplayNames: [
        "c_options"
      ]
    }
[...]