/**
 * Display-only softener for mid-stream markdown.
 *
 * While tokens are still arriving, incomplete markers (`**bold`, an open
 * fence, a half-finished link) would otherwise render as raw punctuation —
 * the hard "breaking" flash. This closes a small set of common unfinished
 * constructs so the parse looks settled; the SOURCE string is never mutated
 * (callers pass the softened copy only into the markdown parser).
 *
 * When the real closers land, the softened and true parses converge and the
 * crystallize breath covers the remount.
 */
export declare function softenStreamingMarkdown(source: string): string;