fix: resolve 17 confirmed bash-parity drifts from port review

Adversarial parity review of every ported action against its bash source
confirmed 17 real behavioral drifts (of 22 claimed); all fixed here:

- tiers/chown: defaults were compositions/apex/tierN (one level too deep);
  now the tier roots. shared/ base reset is non-recursive again.
- compose: --dry-run was swallowed by argparse.REMAINDER; now stripped.
- host.write_file: rendered files land 0644 (tempfile's 0600 made fresh
  systemd units/crowdsec configs owner-only).
- systemd.deploy_units: top-level non-hidden files only.
- ufw: missing docker/host config dir exits 66; missing /etc/ufw target
  aborts; empty rules dir warns; dotfile .rules excluded.
- sync/packages: Telegram error-trap parity and failed notify exits 1.
  Same notify-failure exit for backup/run and sync/repository.
  repository regains the node-dir guard.
- tiers/useradd: no more secret-bearing .env.bak per run.
- tiers/link: EOF on confirm prompt declines and continues.
- extract-traefik-certs: sudo mkdir inside the notify envelope.
- generate-happ-subscriptions: realpath parent-exists guards + docker check.
- configure/crowdsec: bouncer install goes through install_packages.
- lint-docker-compose: malformed/unreadable anchor-IP inputs are lint errors.
- core compose: APEX_RESTIC_REPOSITORY now ?error; RESTIC_COMPRESSION
  per-node via APEX_RESTIC_COMPRESSION (default auto).
- sys.service_exists line-anchored; tpl docstring corrected.

actions/utils/lint-docker-compose.py

@@ -50,12 +50,22 @@ def _validate_anchor_ips(ctx) -> int:
         f = os.path.join(comp, proj, "docker-compose.yml")
         if not os.path.isfile(f):
             continue
-        for m in re.finditer(r"ipv4_address:\s*([0-9.]+)", open(f).read()):
+        try:
+            text = open(f).read()
+        except OSError as e:
+            ctx.log.error(f"Cannot read {f}: {e}"); rc = 1
+            continue
+        for m in re.finditer(r"ipv4_address:\s*([0-9.]+)", text):
             ip = m.group(1)
+            try:
+                addr = ipaddress.ip_address(ip)
+            except ValueError:   # e.g. "10.0.0." — a lint error, not a crash
+                ctx.log.error(f"Malformed anchor IP {ip!r} in {proj}"); rc = 1
+                continue
             if ip in seen:
                 ctx.log.error(f"Duplicate anchor IP {ip} in {proj} and {seen[ip]}"); rc = 1
             seen[ip] = proj
-            if subnet is not None and ipaddress.ip_address(ip) not in subnet:
+            if subnet is not None and addr not in subnet:
                 ctx.log.error(f"Anchor IP {ip} ({proj}) not in node subnet {subnet}"); rc = 1
     if rc == 0:
         ctx.log.info("Anchor IP validation passed.")