Parses the loose invites file (name,url per line; blank lines and
comments skipped), normalizes names (vpsecops -> vp-secops), extracts
email/username/displayName from the invite URL query params, and
merges into agents.yaml. Unknown agents are appended phase1-only.
Duplicate invite tokens are skipped loudly (stale copy-paste guard)
while valid entries still merge. Verified live: caught the svp-knel
line reusing coo's token, merged 5 agents, appended vp-investing and
vp-trading.
