nix: gate hive-c0re on deploy.hive-controller.enable, drop hyperhive.enable

`services.hyperhive.enable` and `services.hyperhive.c0re.enable` are gone.
One switch, `services.hyperhive.deploy.hive-controller.enable` (default
false, as the old toggle was), now gates hive-c0re and hive-priv. Both old
paths are `mkRenamedOptionModule` shims in deploy.nix, so a host config
that still sets either evaluates as before and gets a rename warning.

Every other read of the old toggle is resolved, including the 29 made
through the `hyperhiveCfg`/`hiveCfg` aliases:

- Dropped: each swarm service and its glue keeps only its own deploy
  toggle (authelia, bao and its PKI glue, grafana, victorialogs,
  victoriametrics, the secret publisher, swarm-ca, the OIDC client rows,
  the controller/nats/matrix-ctl/publisher/services-issuer identities),
  the forge, and the `domain` deprecation warning.
- To deploy.hive-controller.enable: the queue-agent credential reader and
  its assertion, which feed hive-c0re and write under its state dir, plus
  their policy-order entry; the network identity assertions; hive-tls's
  two writes into hive-c0re's environment.
- hive-tls runs where the gateway runs self-signed
  (`gateway.enable && useSelfSigned`), not on every host.
- The matrix appservice-token reader and its assertion stay on
  `deploy.matrix.enable` plus their client-identity checks. They read
  deploy.matrix's token file and registration script; their deploy.bao
  inputs are the client-half options a hive sets to read a store it does
  not run, so gating on deploy.bao.enable would drop the tested
  remote-reader case.
- The `hiveName` assertion moves from hive-network.nix to hyperhive.nix
  and fires wherever the hive, the store or the homeserver runs: each
  turns the name into an identifier with no fallback.

On a host with `deploy.allSwarmServices` and no hive, the documented
services-host recipe, authelia, bao, grafana, victorialogs,
victoriametrics, the OIDC client rows and the hive CA now render; before,
the old toggle being off left them out.

Refs #4500

nix/host-modules/default.nix

@@ -1,7 +1,8 @@
 # The full hyperhive host stack, pulled together in one place — this
 # is what the flake exports as `nixosModules.default` (wrapped with
 # the package/source wiring; see flake.nix). One import covers
-# everything; `services.hyperhive.enable = true` turns the stack on.
+# everything; `services.hyperhive.deploy.hive-controller.enable = true`
+# runs a hive on this host.
 #
 # Every swarm needs the forge — hive-c0re mirrors every agent's applied
 # config repo into it and it's the canonical store for the meta flake
@@ -9,7 +10,7 @@
 # runs it (derived from `deploy.allSwarmServices`, see
 # ./swarm-required-services.nix). hive-matrix is opt-in (off by default). All
 # subsystems rely on `services.hyperhive.domain`, which is required
-# (asserted in hive-network.nix) whenever hyperhive is enabled.
+# (asserted in hive-network.nix) wherever this host runs a hive.
 {
   imports = [
     ./hyperhive.nix