Every agent now connects to the queue and reads logs with its own secret
from the store (#5181), so the per-hive `hive-<h>-agent` OIDC client has
no reader left. Remove it end to end:
- hive-c0re no longer forwards `hive-queue-agent-{secret,client-id}` into
containers, and no longer forwards HIVE_AGENT_OIDC_TOKEN_ENDPOINT; the
agent module that loaded them (nix/agent-modules/queue.nix) is gone, its
options refused with a removal message.
- The host reader (glue-queue-agent-credential.nix, swarm-bao-queue-agent),
its store role and policy unit (swarm-bao-queue-agent-policy), its PKI
leaf and the deploy.bao.queueAgent* / queue.agentCredentialDir options
are gone; the options are refused with a removal message.
- authelia mints no `hive-<h>-agent` client, and swarm-secret-publish no
longer writes swarm/hives/<h>/queue/agent.
- swarm-secret-client drops queue::agent_client_path / queue::Credential.
- HIVE_AGENT_NATS_URL is now gated on the agents' queue address alone.
The log store's authelia check stays for operators. swarm-nats-auth still
refuses a `-agent` client id; that refusal and `agentClientSuffix` are left
for a follow-up.
Refs #4459
Refs #4765
swarm-secret-publish and its path unit now run inside authelia's container,
beside the mint, and read each client secret at the path authelia writes it.
The host unit and host path unit, which read the secrets through the
container's root on the host, are gone, and so is
deploy.authelia.hostClientSecretDir, which only they read. The publisher keeps
its store identity, the secret-publisher leaf. The host hands the leaf and the
store's CA into the container as nspawn system credentials, and the unit loads
them; where this host mints the leaf, the container waits for swarm-bao-pki.
Authelia does not wait for the publisher, which retries every 30 seconds while
the store is down.
The container also runs the journal forwarder the other service containers
run, pushing to a receiver of its own on the swarm collector (serviceProducers
swarm-authelia) as a new machine OIDC client (swarm.authelia.otel.clientId)
that authelia registers for itself and the publisher carries to the store. The
fetch unit reads it back under the publisher's leaf, also handed to it as a
system credential, so the swarm-secret-publisher policy gains read on that one
leaf; its stanza keeps create and update, which the exact path would otherwise
take from the services/* prefix. Without the leaf the forwarder is off.
The container drops --link-journal=host, and the host collector stops reading
it. The services' "nothing at <path>" errors name the publisher in authelia's
container.
