/** Strict calendar date — the grammar the feedback ledger's `date` field
 *  already enforces (YYYY-MM-DD), plus calendar validity (2026-02-30 is a
 *  grammatical non-date, still not a date). Returns the trimmed value, or
 *  null when it is not a date. No locale guessing: "Jan 8, 2024" is null. */
export declare function parseDateCell(raw: string): string | null;
/** Normalize a rows-mode progress cell onto 0..1. THE RULE: a number at or
 *  below 1 is a fraction of 1, a number above 1 is a percentage of 100
 *  ("0.4" and "40" both mean 40%; "1" means done). Outside 0..100 the value
 *  clamps and says so, so a bar can never overflow its own geometry.
 *  Returns null for an empty cell (no progress bound to this row — not a
 *  mistake), `{ error: true }` for a non-number (the caller reports it). */
export declare function tlProgressFrac(raw: string): {
    frac: number;
    clamped: boolean;
} | {
    error: true;
} | null;