Pending Outreach Referrals

Referrals waiting on Rooster's content-creation/outbound skill -- the same hat named in docs/01_decisions/ONE_ROOSTER_MANY_SKILLS.md ("content creation and outbound messaging").

Backed by ladder_service.list_pending_referrals_for_rooster -- the SAME table GET /api/sales/referrals/pending already reads for a human, reshaped into the {"conversations": [{"id": ...}, ...]} contract tools/rooster_worker/worker.py's fetch_pending expects, MINUS any referral Rooster already filed a proposal for -- see that function's own docstring for why (without it, the same referral re-drafts every ~10s poll tick forever). Rooster may draft the next message to the referred contact (rooster-outreach skill) and file it as a proposal; it may never call confirm_referral itself -- a machine-parsed name is not acted on until a human agrees (ladder_service.record_referral's own docstring).