`swarm.victorialogs` (what the log store is to every hive: container name,
domain, port) moves to nix/host-modules/swarm-victorialogs-service.nix,
together with the only two helpers it reads, `swarmDomain` and
`domainBase`. Everything else -- the `deploy.victorialogs` options, the
whole `config` block including `containers.swarm-victorialogs`, the file
header and the helpers only they read (`swarmAuthRequest` among them) --
stays in nix/host-modules/swarm-victorialogs.nix, which default.nix now
imports alongside the new file.
`hyperhiveCfg` (an alias for `config.services.hyperhive`, not an option) is
read by both halves, so it is duplicated into the service file rather than
shared.
A pure move: option paths, option definitions and config are unchanged
apart from the comment above the `deploy.victorialogs` options, which now
names the file `swarm.victorialogs` lives in. Fixtures enabling the store
evaluate to the same host and container toplevel derivations before and
after.
Refs #3742
