docker-compose brings up PostgreSQL 16 with pgvector and Redis 7 on
non-standard host ports so it never collides with an existing local database.
scripts/smoke.sh is the proof: compose, migrate, boot the API, issue a token,
call the real DeepSeek API and print the resulting ob_ai_call and bl_ledger
rows. services/vision and services/matting are placeholders noting that the
local RTX 5090 makes BiRefNet and RTMPose developable without cloud GPU.