A 429 now starts the credit cooldown from its headers and drops the body
unread, so a stalled or oversized 429 cannot skip the governor; an oversized
snapshot is not retried. A 429 without retry-after now waits the intended
2 minutes (headers.get() returns null, which Number() read as 0 s). Adds
oversized-stream tests for OpenSky, adsb.lol, CelesTrak and TomTom that fail
on main, names the six reads in the changelog, and corrects the docs on
what was already bounded.