Review follow-up: bare \b401\b / \b402\b / \b429\b / \b5xx\b matched any
3-digit token in error text ('line 502', 'took 429 ms'), and server_error
misfires feed AUTO_RETRYABLE — a supervisor could auto-retry a permanent
local failure. Numeric rules now require an 'error code:'/'status:'/'http'
prefix; phrase alternatives (rate limit, server error, overloaded, out of
funds) unchanged. Adds parametrize rows for the false-positive guards and
the previously untested branches (bare 'status: 401', 'upstream server
error', 'model_not_found').
kshitij