refactor(v2): move setup/groups.ts off trunk + drop pino dep

setup/groups.ts is whatsapp-only — its inline syncScript imports baileys
and pino to fetch group metadata via Baileys.groupFetchAllParticipating.
On trunk it was a no-op for non-whatsapp users (returned early without
auth) and the only thing keeping pino alive.

Removed:
- setup/groups.ts (lives on `channels` branch; restored by /add-whatsapp-v2)
- `groups` STEPS entry from setup/index.ts
- pino from package.json (no longer used outside the moved file)

/add-whatsapp-v2 skill updated to copy setup/groups.ts and register both
groups + whatsapp-auth in setup/index.ts STEPS, install pino@9.6.0 along
with baileys + qrcode.

Verified: build clean, 326 host tests pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

setup/index.ts

@@ -12,7 +12,6 @@ const STEPS: Record<
   timezone: () => import('./timezone.js'),
   environment: () => import('./environment.js'),
   container: () => import('./container.js'),
-  groups: () => import('./groups.js'),
   register: () => import('./register.js'),
   mounts: () => import('./mounts.js'),
   service: () => import('./service.js'),