/**
 * Picks a block's per-variant config from its `layout.ts` table by the backend
 * `instance_slot.variant`, falling back to `fallback` for anything the table does not own.
 *
 * `Object.hasOwn` rather than a bare index: the key is backend-controlled, and an inherited
 * name like `constructor` would otherwise return a truthy non-config that `??` lets through.
 * Unknown variants warn, like `createVariantBlock`, so a backend typo or a new server variant
 * is visible instead of silently degrading.
 */
export declare const resolveVariantConfig: <K extends string, C>(table: Record<K, C>, variant: string | null | undefined, fallback: K, blockName: string) => C;