[Dash] register email senders & domains #94

Description

When a project has email set up, Juno still can’t answer “what addresses can I send from?” or “is my domain verified?” in the dash.

What this even is: SendGrid (behind Juno email) needs (1) a sender — a from-address like noreply@club.com that’s allowed to send — and (2) a domain — DNS proof that you own club.com. Config (the SendGrid API key on the project) is separate and already has UI. This ticket is the sender/domain part.

What exists today

• Dash /projects/[id]/services/email — email config + a little analytics chart. No senders/domains UI.
• Gateway already has create/verify, no list:
  • POST /email/register-sender
  • POST /email/register-domain
  • POST /email/verify-domain
  • GET /email/config/:id, POST /email/setup, etc.
• Docs: local http://localhost:8888/docs. Auth same as the rest of the dash (JUNO_API_KEY / JUNO_BASE_URL).

What to build

Under Email (tab or section on the email page — David’s mock had a “Configurations” tab; match whatever fits current nav):

1. Form to register a sender (calls register-sender)
2. Form to register a domain + verify it (calls register-domain / verify-domain) — show whatever DNS / status the API returns so people aren’t guessing
3. Pass the project explicitly (juno#226)

There’s no GET for “list my senders/domains” on the gateway right now. If you want tables of existing ones (like file buckets), that’s a small backend add (proxy SendGrid verified_senders / whitelabel domains) — ask before boiling the ocean. v1 can ship as register + verify + clear success/error even without a list.

Don’t continue dash#85 / juno#251. Start fresh.

Local: Juno + dash, and a SendGrid key on the project email config or you can’t register anything real.

Acceptance Criteria

• From a project’s email area I can register a sender and see success/failure clearly
• I can register a domain and verify it, with enough UI to know what happened
• Project is passed explicitly (no wrong-project silent bugs)
• You didn’t revive the old PRs

Other Notes

Mid. Closest old writeup is juno#249 if you want the Spring mock screenshot — ignore the “must add e2e + SDK + personal SendGrid demo” fluff unless we say otherwise.