The original migration used a fragile add-copy-drop-rename pattern with
_jsonb casts that silently failed, leaving the embedding column as text.
Replace with a direct ALTER COLUMN TYPE ... USING embedding::vector(1536)
that is fully idempotent and handles all partial states from previous
failed attempts.
- docker-compose.yml: switch postgres:16-alpine to pgvector/pgvector:pg16
- migration: rewrite with IF NOT EXISTS guards, DO block for safe
text→vector(1536) conversion, handles partial/re-run states
- schema.prisma (both): add @default(now()) on NoteEmbedding.updatedAt,
sync mcp-server embedding type to Unsupported("vector(1536)")
- deploy.yaml: add docker compose pull postgres before build
