/**
 * [WHO]: installWarningGuard — mirrors Node process warnings into the diagnostics bus
 * [FROM]: Depends on utils/diagnostics.js (isDevRuntime, reportDiagnostic)
 * [TO]: Consumed by main.ts at CLI startup (user mode)
 * [HERE]: utils/warning-guard.ts - warning observability only; never suppresses
 *
 * Design history: an earlier in-main.ts version monkey-patched process.emitWarning
 * and removed Node's default 'warning' listeners to hide MaxListenersExceededWarning
 * in user mode. That hid real listener leaks. Empirically (Node 20+), adding a
 * 'warning' listener does NOT disable Node's default stderr printer, so nothing
 * needs to be silenced for observability — this module only mirrors, never swallows.
 */
/**
 * Mirror Node process warnings into the unified diagnostics bus WITHOUT
 * suppressing them. Node's default stderr printer keeps running (adding a
 * listener does not disable it), so listener leaks and deprecations stay
 * visible to users.
 *
 * DEP0190 (spawn with shell:true + args array; Node 24+) is mirrored, not
 * swallowed: this repo's own spawn sites already use the non-deprecated form.
 * If a dependency starts triggering it, diagnostics data will identify the
 * source and a targeted, documented suppression can be added then.
 *
 * No-op in dev runtime (reportDiagnostic would double-print there).
 */
export declare function installWarningGuard(): void;