ConstComma-separated examples of typical json-shape outputs
for the specific tool (e.g. "counts, groupings, hex bins, centroids").
OptionalchartLabelExample: stringOptional inline code snippet illustrating a
multi-line string[] label using the tool's domain. Omitted when empty.
Builds the shared "return value" blurb for the analyse-* tools'
codefield. Encodes the JSON-only contract, the Chart.js config shape, and thestring[]-label workaround for tooltip-callback use cases.