Pre-seeds the `dokku/install_default_site` debconf answer to `true` so the dokku postinst installs `/etc/nginx/conf.d/00-default-vhost.conf` during image build. Without this, debconf returned an empty value in non-interactive docker builds, the postinst's `setup-default-site` short-circuited, and nginx had no listener on port 80 - which left the readiness sentinel untouched and the container stuck unhealthy.
The official dokku/dokku image gains a HEALTHCHECK directive backed by a loopback-only HTTP endpoint at `127.0.0.1:18080/_dokku/health`. The endpoint reports 200 once first-boot bootstrap finishes, sshd and nginx are accepting connections, and `dokku ps:restore` completes; otherwise it returns 503. Changes are scoped to the Docker overlay and Dockerfile so debian-package installs are unaffected.
The ppa:cncf-buildpacks/pack-cli launchpad source is currently down, breaking the runtime image build and any bats run that calls install_pack. Pack is now tracked in contrib/dependencies.json and pulled from the buildpacks/pack GitHub release tarball, matching how other binary deps are managed. update-deb-dependencies gains hyphen-aware word-boundary matching so single-word names like pack cannot accidentally rewrite unrelated debian/control lines, keeping pack out of the package's hard requirements.
On newer Ubuntu Noble, cron (among other things) has a transitory dependency on systemd, forcing our systemd/runit detection to fail. This change allows overriding the detected init on Ubuntu systems, ensuring we always do the right thing when interacting with init.
The systemd package was installed by default for some reason, causing issues when interacting with init processes. Specifically, we would detect systemctl on runit systems and incorrectly invoke that when restarting processes.
Additionally, ensure the copied binaries are executable.
Closes#7089
This makes the installation a bit more secure by ensuring a user does not accidentally expose a way for unauthorized users to add new ssh keys to the system.
Additionally, this removes the extra HOSTNAME file to make the initial install process easier (that file was not modifiable by any dokku commands.
Closes#2247
