install_coturn (services/coturn.sh) cd's into $DOCKER_DIR/coturn and never
restores the caller's original working directory. A consumer that chain-
installs coturn mid-flow (e.g. asterisk.sh, already cd'd into its own
install directory) returned from ensure_coturn_user still sitting in
coturn's directory, then went on to write its own docker-compose.yml/.env
there instead of its own directory — clobbering coturn's compose file and
leaving the consumer's directory without one. The consumer's later
`docker compose up --build` then failed with "Dockerfile: no such file or
directory", since the Dockerfile was correctly in the consumer's directory
but the misplaced compose file (and the build) were not.
ensure_coturn_user now saves/restores the caller's cwd around the
install_coturn call, fixing this for every consumer (asterisk, mattermost).
Also fold cloud-init.sh's contents into a collapsible README section so
it's copy-pasteable straight from the repo instead of requiring a separate
file download.
Claude
32240e18f9