Consumers (e.g. thepeach) need a PULLABLE tidaldb image — not every dev has the
source for a compose `build:` context. Publishes registry.threesix.ai/tidal/standalone
as a manifest list: linux/amd64 (Linux/CI) + linux/arm64 (Apple-silicon Macs),
defaulting to STANDALONE mode (:9400, --data-dir /data) so it drops into a consumer's
docker-compose like postgres.
Hybrid build because `rustc` SIGSEGVs under QEMU (an in-container amd64 cross-build on
an arm64 host fails):
- amd64: docker/standalone/amd64.Dockerfile packages the HOST cross-compiled x86_64
binary (the proven build-release path; trixie-slim for glibc 2.41/libmvec) — apt+COPY only.
- arm64: native in-container build from docker/standalone/Dockerfile.
- scripts/build-standalone-image.sh stitches both into one manifest list (:m12 + :latest).
Verified: pulled :m12 (arm64), booted standalone, GET /health -> {ok:true,mode:standalone}.