Label Path

Optional `tx.Expression` (same shape as metricPath) evaluated on each referenced resource to its display text (instead of its rdfs.label). On a ReferenceList it switches the band from inline comma-joined links to detailed rows, each with a chip-tier SemanticSvg icon — e.g. a `tx.PropertyRead` of evidenceStatement so evidence shows its statement rather than its key. On a TimePlot it supplies the native hover tooltip per point.