refactor: rewrite to s6-overlay new service format

build: update CI pipeline refactor: base image refactor: rewrite to s6-overlay new service format build: check-new-tags only on main branch fix: file permissions build: fix job name docs: update README build: fix code format ci: fix job stage ci: add shellcheck manual trigger ci: fix pipeline ci: fix pipeline variable ci: fix shellcheck find files chore: fix shellcheck source ci: fix to allow shellcheck to load external sources fix: shellcheck