🗃️ rootfs: shield internal entrypoint PID files from /run/*.pid sweeps 🗃️

Update the embedded entrypoint copies in rootfs/ to match the
upstream template change. Internal state files renamed to dotfiles
so they're not matched by `/run/*.pid` cleanup globs:
- /run/init.d/entrypoint.pid -> /run/.entrypoint.pid
- /run/no_exit.pid -> /run/.no_exit.pid
- /run/backup.pid -> /run/.backup.pid
- /run/__start_init_scripts.pid -> /run/.start_init_scripts.pid
Per-service PIDs in /run/init.d/ are unchanged.

rootfs/usr/local/bin/entrypoint.sh
rootfs/usr/local/etc/docker/functions/entrypoint.sh
rootfs/usr/local/etc/docker/init.d/00-aria2c.sh
rootfs/usr/local/etc/docker/init.d/zz-nginx.sh
rootfs/usr/local/share/template-files/config/env/default.sample
rootfs/usr/local/share/template-files/config/env/examples/zz-entrypoint.sh

rootfs/usr/local/etc/docker/init.d/00-aria2c.sh

@@ -46,7 +46,7 @@ __script_exit() {
 SCRIPT_NAME="$(basename -- "$SCRIPT_FILE" 2>/dev/null)"
 # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 # exit if __start_init_scripts function hasn't been Initialized
-if [ ! -f "/run/__start_init_scripts.pid" ]; then
+if [ ! -f "/run/.start_init_scripts.pid" ]; then
 	echo "__start_init_scripts function hasn't been Initialized" >&2
 	SERVICE_IS_RUNNING="no"
 	__script_exit 1