caddy + pihole: make both boot-persistent and self-healing

Caddy left compose.yaml for a quadlet unit (caddy.service): joins
dankclaw_default for container-name upstreams, Pull=never for the local-only
image, Porkbun credentials via /home/dank/Containers/caddy/env written by
deploy from .env, bare-IP-catch-all health check. deploy_caddy installs,
enables, and starts the unit after retiring the bare container (state is in
host volumes).

Pi-hole: the repo now owns the sysctl drop-in
(dankclaw/pihole/sysctl/99-dnsmasq.conf, ip_unprivileged_port_start=53);
deploy_pihole installs it to /etc/sysctl.d/, stages conflicting later-sorted
drop-ins in the home trash, and applies 'sysctl --system' (the boot code
path). This fixes the 2026-08-26 crash loop (port-53 bind denied, restart
counter 1645) caused by a second drop-in resetting the value to 80.

Tests: new caddy_quadlet.bats seam; caddyfile/deployment_flow assertions
repointed from the removed compose service to the quadlet; pihole.bats pins
the sysctl drop-in and its deployment; test-changed.sh routes dankclaw/caddy/
and the pihole subtree to their seams. Docs: Caddy, Pi-hole, Dankclaw Stack,
work log.

scripts/test-changed.sh

@@ -104,6 +104,16 @@ for path in "${CHANGED[@]}"; do
             add_test tests/searxng_quadlet.bats
             add_test tests/deployment_scoping.bats
             ;;
+        # Caddy left compose.yaml on 2026-08-26 for a quadlet; caddyfile.bats
+        # now asserts against the quadlet itself. Route every change under
+        # dankclaw/caddy/ to both seams (this block must precede the
+        # dankclaw/*.container glob, which would otherwise swallow the unit).
+        dankclaw/caddy/*)
+            add_test tests/caddy_quadlet.bats
+            add_test tests/caddyfile.bats
+            add_test tests/docs_completeness.bats
+            add_test tests/deployment_scoping.bats
+            ;;
         dankclaw/*.container|dankclaw/*.network)
             add_test tests/open_webui_quadlet.bats
             add_test tests/pihole.bats
@@ -116,7 +126,7 @@ for path in "${CHANGED[@]}"; do
         # their seam tests. The pihole-specific block must come first: shell
         # case matches the first pattern, and dankclaw/pihole/quadlet/*.container
         # also satisfies the dankclaw/*/quadlet/*.container fallback.
-        dankclaw/pihole/addn-hosts|dankclaw/pihole/env.example|dankclaw/pihole/quadlet/*.container|dankclaw/pihole/quadlet/*.network)
+        dankclaw/pihole/*)
             add_test tests/pihole.bats
             add_test tests/docs_completeness.bats
             add_test tests/deployment_scoping.bats