The swarm collector's journald receiver read only the units listed in
`services.hyperhive.swarm.otel.journaldUnits`. A unit nobody listed
never reached the store, and a misspelt entry shipped nothing without
an error. The list existed to keep an operator's desktop session out of
a store every swarm operator can read, but the receiver can only match
positively, so the only way to express "not user sessions" was to name
every service instead.
The receiver now reads the whole host journal, and a new
`filter/exclude-user-sessions` processor in the `logs/<swarm>` pipeline
drops records whose `_SYSTEMD_SLICE` is `user-<uid>.slice` (session
scopes and `user@<uid>.service`). The per-hive `logs/<hive>` pipelines
carry agent-container journals only and get no filter.
`journaldUnits` is removed with `mkRemovedOptionModule`, together with
its non-empty assertion and the entry each host module added. The four
module-eval membership checks go with it, replaced by one structural
case in swarm-otel-core.
Closes#3646
`services.hyperhive.gateway.enable`, `gateway.dns.enable` and
`network.enable` replace the `hyperhive.enable` gate on all three. Each
defaults to false; the modules that need one assert it with `mkDefault
true` from inside the guard their own deployment already carries, and
`swarm-required-services.nix` — the module that owns what the
swarm-services toggle implies — asserts all three explicitly.
hive-c0re asserts all three unconditionally, so an ordinary hive keeps
getting them with no opt-in: it is the host's only knowledge that agent
containers exist.
The resolver moves to its own `hive-gateway/dns.nix` so it can be gated
without reindenting the nginx half of the module.
Reinstates `network.enable`, dropping its `mkRemovedOptionModule` shim.
A config still carrying `network.enable = false` from before the removal
now switches the bridge off instead of failing eval.
Also deletes a duplicate `centralToggleOff` fixture in nix/module-eval.nix.
Two sibling slices added it independently (c5f60fd5, ce3b3d94); the merge
was textually clean and left `main` failing to evaluate at all, so this
file could not be gated without removing one.
