OpenResty running as openflare can no longer write pid or client/proxy temp
paths under the OpenResty install prefix. Templates and apply-time rendering
now use __OPENFLARE_PID_PATH__ and __OPENFLARE_NGINX_CACHE_DIR__ under
data_dir/var/run and data_dir/var/cache/nginx, with legacy pid path patched
at apply. Consolidate runtimeuser path helpers into the main package file so
IDEs resolve references across build tags.
Introduce the shared openflare service account for the agent process and
OpenResty workers, normalize data_dir ownership on startup, and ensure
managed paths are chowned with 0755/0644 during sync and apply. Docker
entrypoint fixes volume ownership before dropping privileges; local systemd
install runs the service as openflare with CAP_NET_BIND_SERVICE.