/**
 * isNothingToCheck recognises a gate command that failed ONLY because there was
 * nothing for it to check yet — not because the code is wrong. In a TDD-staged
 * plan an early stage legitimately precedes its source or test files, so:
 *
 *   - `tsc --noEmit` emits TS18003 ("No inputs were found") when zero files
 *     match its include globs. tsc emits this ONLY in the empty-input case; it
 *     never coexists with a real type error, so matching it cannot mask one.
 *   - `bun test` prints "No tests found!" and exits non-zero when the suite is
 *     empty — the measured twin of the existing EMPTY_SUITE_NOTE prompt carve-out.
 *
 * ADR 0001 made the MEASURED exit code authoritative (a green LLM verdict cannot
 * override a non-zero gate). That is correct for real failures but wrong for the
 * empty-tree state, where the non-zero exit means "nothing here yet", not "the
 * code is broken". This predicate lets the gate treat that one state as
 * pass-equivalent, scoped tightly so a genuine type error or failing test still
 * FAILs.
 *
 * Defensive scoping: TS18003 only counts as nothing-to-check when it is the SOLE
 * TypeScript diagnostic — if any other `error TSxxxx` is present, real work is
 * being checked and the gate must fail.
 *
 * Pure (string in, boolean out) so it is unit-tested directly.
 */
export declare function isNothingToCheck(output: string | undefined): boolean;