Add pilotctl verify status with offline check and how-to

[TeoSlayer]

Lets a user see whether their own address is verified, with a how-to hint when it is not. Deliberately low-key: a single explicit command, no verified marks scattered across other output.

pilotctl verify status (also bare pilotctl verify)

• Resolves the node's own ID (from the daemon, or --node <addr|id>), reads its badge from the registry (untrusted transport), and verifies it offline via badgeverify.VerifyForNode against the pinned issuer key — never trusting the registry's word.
• States:
  • verified — ✓ Verified via <provider> (since <date>)
  • badge_present_unvalidated — a badge is on file but the issuer key is not pinned in this build (fail-closed), so it cannot be validated.
  • not_verified — prints the two-step how-to (pilot-verify verify … then pilotctl verify --badge …).
• JSON and human output. pilotctl verify --badge … --badge-sig … still submits, unchanged.

Note: the handshake intentionally does not carry the badge — verification is a property of the address, surfaced on demand. Apps check verification via the offline badgeverify helper (library-level today; SDK wrappers later).

Tests

• not-verified → how-to hint present; badge-present-but-placeholder-key → fail-closed (verified=false), provider still surfaced; human output shows the headline + how-to.
• go test -race ./cmd/pilotctl/ green; gofmt + vet clean.