nix: split swarm-victorialogs into service and deploy-mode files

`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

nix/host-modules/default.nix

@@ -53,6 +53,7 @@
     ./swarm-otel.nix
     ./swarm-snapshot-store.nix
     ./swarm-ui.nix
+    ./swarm-victorialogs-service.nix
     ./swarm-victorialogs.nix
     ./swarm-victoriametrics-service.nix
     ./swarm-victoriametrics.nix

nix/host-modules/swarm-victorialogs-service.nix

@@ -0,0 +1,66 @@
+# The swarm's log store as every hive sees it: the name it answers on and its
+# port, identical on every host. What the host running it decides, and the
+# container itself, are in ./swarm-victorialogs.nix.
+{
+  lib,
+  config,
+  ...
+}:
+let
+  hyperhiveCfg = config.services.hyperhive;
+  swarmDomain = hyperhiveCfg.swarm.domain;
+
+  # Total on a null swarm domain for the same reason every sibling module is:
+  # the required-domain assertion in hive-network.nix should be what an
+  # operator sees, not a coercion error from here.
+  domainBase = if swarmDomain == null then "invalid" else swarmDomain;
+in
+{
+  # What the store IS from any hive's point of view: the name it answers on and
+  # the port. `enable`, `package` and `retentionPeriod` are decisions of the
+  # host that runs it and live under `deploy.*`.
+  options.services.hyperhive.swarm.victorialogs = {
+    machine = lib.mkOption {
+      type = lib.types.str;
+      readOnly = true;
+      default = "swarm-victorialogs";
+      description = ''
+        Container name. Read-only: the name appears in host paths and in
+        `machinectl`, so it is a fact other modules may read rather than a
+        knob.
+      '';
+    };
+
+    domain = lib.mkOption {
+      type = lib.types.str;
+      default = "logs.${domainBase}";
+      defaultText = lib.literalExpression ''"logs.''${services.hyperhive.swarm.domain}"'';
+      description = ''
+        Name the gateway serves this on, behind the same authelia
+        `auth_request` gate as the swarm UI's own vhost. A sibling of the
+        swarm's other service names, so the swarm-services sub-CA can
+        issue for it — see `hive-tls.nix` for why a service name being a
+        sibling rather than a child decides which CA may sign it, and
+        `swarm.nix`'s `serviceDomains'` for where this name has to be
+        registered for that to actually happen.
+      '';
+    };
+
+    port = lib.mkOption {
+      type = lib.types.port;
+      default = 9428;
+      description = ''
+        Loopback port the store listens on. Upstream's default, kept
+        because there is no reason to move it and a familiar number is
+        one less thing an operator has to look up.
+
+        ⚠️ Every swarm container shares the host's network namespace, so
+        this is a swarm-wide claim rather than a per-container one — two
+        modules picking the same number collide at runtime with no bind
+        error and nothing in any log. `state/eval-port-collisions.sh`
+        checks the class.
+      '';
+    };
+
+  };
+}

nix/host-modules/swarm-victorialogs.nix

@@ -40,12 +40,6 @@ let
   networkCfg = config.services.hyperhive.network;
   hyperhiveCfg = config.services.hyperhive;
   gatewayCfg = hyperhiveCfg.gateway;
-  swarmDomain = hyperhiveCfg.swarm.domain;
-
-  # Total on a null swarm domain for the same reason every sibling module is:
-  # the required-domain assertion in hive-network.nix should be what an
-  # operator sees, not a coercion error from here.
-  domainBase = if swarmDomain == null then "invalid" else swarmDomain;
 
   # Copy of `swarm-ui.nix`'s own `swarmAuthRequest` — not shared code because
   # this vhost needs exactly the two locations that reference it (`/` and the
@@ -63,54 +57,10 @@ let
   privateNetwork = false;
 in
 {
-  # What stays here is what the store IS from any hive's point of view: the
+  # What the store IS from any hive's point of view, the name it answers on and
-  # name it answers on and the port. `enable`, `package` and
+  # the port, is `swarm.victorialogs` in ./swarm-victorialogs-service.nix.
-  # `retentionPeriod` are decisions of the host that runs it and live under
+  # `enable`, `package` and `retentionPeriod` are decisions of the host that
-  # `deploy.*`.
+  # runs it and live under `deploy.*`.
-  options.services.hyperhive.swarm.victorialogs = {
-    machine = lib.mkOption {
-      type = lib.types.str;
-      readOnly = true;
-      default = "swarm-victorialogs";
-      description = ''
-        Container name. Read-only: the name appears in host paths and in
-        `machinectl`, so it is a fact other modules may read rather than a
-        knob.
-      '';
-    };
-
-    domain = lib.mkOption {
-      type = lib.types.str;
-      default = "logs.${domainBase}";
-      defaultText = lib.literalExpression ''"logs.''${services.hyperhive.swarm.domain}"'';
-      description = ''
-        Name the gateway serves this on, behind the same authelia
-        `auth_request` gate as the swarm UI's own vhost. A sibling of the
-        swarm's other service names, so the swarm-services sub-CA can
-        issue for it — see `hive-tls.nix` for why a service name being a
-        sibling rather than a child decides which CA may sign it, and
-        `swarm.nix`'s `serviceDomains'` for where this name has to be
-        registered for that to actually happen.
-      '';
-    };
-
-    port = lib.mkOption {
-      type = lib.types.port;
-      default = 9428;
-      description = ''
-        Loopback port the store listens on. Upstream's default, kept
-        because there is no reason to move it and a familiar number is
-        one less thing an operator has to look up.
-
-        ⚠️ Every swarm container shares the host's network namespace, so
-        this is a swarm-wide claim rather than a per-container one — two
-        modules picking the same number collide at runtime with no bind
-        error and nothing in any log. `state/eval-port-collisions.sh`
-        checks the class.
-      '';
-    };
-
-  };
 
   # Retention is a property of the store this host runs, not something the
   # swarm has to agree on: it is read only where the container is defined,