/**
 * Measure the rendered pixel width of label text using a Canvas context configured
 * with the same font as shape edge labels (`cvaShapeLabel` / `ShapeLabelPill`).
 *
 * Results are cached per label text. Using Canvas.measureText avoids the forced
 * synchronous layout (reflow) that getBoundingClientRect triggers when called inside
 * a Google Maps onDraw callback — the previous implementation caused ~67ms of blocked
 * main-thread time per draw cycle during zoom (observed in Chrome DevTools trace).
 *
 * Falls back to DOM measurement if canvas is unavailable, and to a character-count
 * estimate in environments without DOM (SSR, jsdom).
 */
export declare const measureLabelWidth: (label: string) => number;