Email organizers once about a draft they haven't published #506

Needs your OK: this is a new email to organizers, and the privacy page changes with it. It also has three decisions for you, listed below. Swap pipeline:proposed for pipeline:ready to have it built. Part of #498.

What happens

Nothing brings an organizer back to an unfinished draft. The only emails are the magic link, the confirmation and the reminder, and the reminder job skips drafts (src/jobs/reminders.ts).

Fix, in outline

• One email per draft, sent a few hours after it was created. Send it only if the signup is still an unpublished draft, has at least one filled-in slot, and hasn't been deleted.
• Content: the same fixed-word headline as the review page ("12 slots · 3 days · 3 people each").
  • The main button, "Check it and publish", opens the review page (Land new drafts on a "Check your signup, then share it" page #502).
  • A second link opens the builder.
  • Both go through sign-in with the deep link kept (as Signed out, a link to a signup in the organizer app sends you to the dashboard after sign-in, not to the signup #259 made work).
• Scheduling: the worker scans for due drafts, as reminderDispatch does. A draft.nudge_sent activity row stops a second send.
• Sending: through EmailTransport, so the console transport is used in dev. The subject line goes in src/email/subjects.ts.

Design: canvas https://claude.ai/artifact/RqcjzCcdSTw5JhbXjm2x5y, row C, artboard "C · Same-day draft email". The canvas is private until shared.

Decisions for you

1. Delay. How long after creating a draft should the email go out (for example, 3 hours)?
2. Turning it off. Can organizers turn it off, and if so, where: an organizer setting, an unsubscribe link, or both?
3. AI connector drafts. Do drafts made through an AI connector qualify? The organizer may still be mid-conversation with their assistant.

Watch for

• Trust docs. Update the privacy page and docs/ in the same PR, and bump "Last updated".
• One worker. Run exactly one worker process, as the reminder emails already require.
• "Email me a link to finish later" on the review page (Land new drafts on a "Check your signup, then share it" page #502) can send this same email right away.

Done when

• A due draft gets exactly one email, and a published, deleted or empty draft gets none. A DB test covers each case.
• The template renders in the worker test.
• The legal pages say organizers may get one email about an unpublished draft.
• pnpm lint && pnpm typecheck && pnpm knip && pnpm test and pnpm test:db pass.

Planned in https://claude.ai/code/session_01AkZbMUc4ej4ed7o5uh6nqr