Profile bundles the crates kei-buddy needs at runtime:
kei-buddy, kei-telegram-webhook, kei-shared, kei-chat-store,
kei-social-store, kei-memory-sqlite, kei-router, kei-llm-bridge-mlx.
Used by keisei-marketplace cloud-init when user clicks 'хочу своего
KeiBuddy' on /keibuddy/setup — Hetzner VPS spawn pulls KeiSeiKit and
runs install.sh --profile=buddy --yes.