- check <source>: open checkUrl, assert loggedInSelector (exit 3 when
  logged out); login <source>: recipe-driven multi-step form flow with
  $USER/$PASS substitution from NH_LOGIN_* env, tab-relocation hardening
  against concurrent harvests, post-login verification
- recipes live in logins/<source>.json; ships digitimes-feed.json
- honors CDP_PORT_OVERRIDE / CDP_PROFILE_OVERRIDE (per-source instances)