0449 — deliveryconsumer kept in the tree but not wired to run

Context. The delivery_consumer loop is a strictly more expensive CURSOR over the same messages, so nothing in the current feature set justifies running it — but the non-FIFO queue work on the roadmap might.

Decision. deliveryconsumer stays in the tree as its own package under pkg/consumer, not deleted, and does not run. It re-earns its place only if non-FIFO queue work needs it.

Consequences. The per-loop package layout makes the eventual outcome cheap either way: reviving it is wiring an existing package, and deleting it is a whole-directory drop. Rejected: deleting now — the roadmap gives it a plausible future, and the layout makes carrying it nearly free.