Stage 7: command-line helpers dsv, duser, dfw, dsys (0.5.0)

- das-helpers replaces the dsv package and adds shared functions in
  /usr/lib/das/helpers.sh (bilingual messages, sudo re-exec, prompts).
- dsv new creates a runit service (command, user, directory, environment,
  svlogd log) and checks it stays up; dsv rm deletes one not from a package.
- duser: list, add (installer groups, --admin, key, password), del, passwd,
  lock/unlock (key logins too), key add|list|rm, groups +/-.
- dfw: allow/deny/status/reload for the tcp_ports and udp_ports sets of the
  inet das table, kept in /etc/nftables.d/dfw.nft and checked with nft -c.
- dsys: info, hostname, timezone, locale, keymap.
- xtools-minimal on both images.
- nftables.conf no longer suggests restarting the nftables service: its
  finish script flushes the whole ruleset, fail2ban's and Docker's included.
- das-server-install 0.2.0 mentions the helpers when it finishes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

srcpkgs/das-helpers/template

@@ -0,0 +1,21 @@
+# Template file for 'das-helpers'
+pkgname=das-helpers
+version=0.1.0
+revision=1
+depends="bash runit sudo shadow openssh nftables kbd"
+short_desc="Das OS helpers: services (dsv), users (duser), firewall (dfw), system (dsys)"
+maintainer="Das <anry.das@gmail.com>"
+license="MIT"
+homepage="https://git.das.org.ua/das/Das-OS"
+# dsv used to be a package of its own
+replaces="dsv>=0"
+provides="dsv-${version}_${revision}"
+
+do_install() {
+	vinstall ${FILESDIR}/helpers.sh 644 usr/lib/das
+	for tool in dsv duser dfw dsys; do
+		vbin ${FILESDIR}/${tool}
+		vcompletion ${FILESDIR}/${tool}.bash-completion bash ${tool}
+	done
+	vlicense ${FILESDIR}/LICENSE
+}