The quadlet .network unit is generator-managed and cannot be enabled; it is
pulled in automatically by the containers that set Wants=/After=searxng-network.
Enable only the three container units. The explicit start of the network is kept
(start works on generated units).
Remove gluetun/searxng/valkey from dankclaw/compose.yaml (they are now
quadlet units) so podman-compose up can no longer fight them for the netns and
port 8081. Add scripts/deploy-searxng-quadlet.sh: an idempotent installer that
copies the units to ~/.config/containers/systemd/, daemon-reloads, enables them
for boot, and starts them in dependency order. Safe to run on first migration
and on every later change.