Hedging fires a second upstream query against the same upstream after
the hedge delay. Rescues packet loss and handshake stalls on flaky
links, but every lookup shows up twice at the provider — silently
halves the headroom for anyone on a quota'd upstream (NextDNS free tier,
Control D, paid Quad9).
Surfaced by #134 (bcookatpcsd), who saw every query duplicated on the
NextDNS dashboard with a single-address DoT upstream. Not a bug — the
feature doing what it says on the tin — but a surprising default.
Flipping the default to 0 makes hedging explicitly opt-in. Users who
want tail-latency rescue on flaky nets add `hedge_ms = 10` (or higher).
No config migration needed; no breaking changes to the API surface.
Also tightens the numa.toml comment so the trade-off is visible at
config time, not retroactively on a provider dashboard.
