provider:resend - domain verification evidence example

[ohad6k]

Provider mapper quest — ~45 min

Add a Resend domain verification evidence example under examples/providers/resend/ showing domain/SPF/DKIM verification state.

Acceptance criteria

• One markdown or JSON file under examples/providers/resend/
• Shows domain verification evidence and what VibeRaven should read
• No live keys, secrets, or customer data

See docs/contributor-quests.md and CONTRIBUTING.md. Comment /take to claim. Small PRs reviewed within 48h.