v0.0.20

Tested against DBOS 2.19.0 — see tested_dbos_version in GET /version and dbos-argus --version. Other DBOS versions may still work; the in-app connection indicator surfaces any schema mismatches.

Note: v0.0.19 was published to PyPI but the docker/release jobs
in the release pipeline failed — pip install dbos-argus==0.0.19
inside the Dockerfile raced PyPI's CDN propagation on the arm64
runner and died with "No matching distribution found", which then
cancelled the rest of the matrix. v0.0.20 carries the same intended
changes plus the pipeline fix, so the Docker image and GitHub
Release exist for this tag.

Fixed

• Release pipeline: each docker-build arch now polls PyPI's simple
  index for the freshly published version (via pip download --no-deps,
  60 attempts × 5s) before invoking buildx, so a wheel that hasn't yet
  propagated to every Fastly edge can no longer race the in-Dockerfile
  pip install.