swarm: say "no queue coordinates", never "a hive with no queue"

The swarm always has exactly one queue; a hive can only lack its
address. Reworded every prose site this PR added that stated or
implied the opposite, to name what is actually absent (coordinates,
credential, or address) instead of the queue itself.

Refs #3805

docs/swarm/README.md

@@ -385,9 +385,9 @@ above, plus `HIVE_AGENT_OIDC_CLIENT_SECRET_FILE` and
 `HIVE_AGENT_OIDC_CLIENT_ID_FILE`, which point into the unit's own credentials
 directory. The last two come from the delivered credential rather than from
 config — see [`secrets.md`](secrets.md#hive-level--one-of-each-per-hive) for
-how it gets there. A hive with no queue sets none of the four and each agent
-logs that it has none; a half-set environment logs an error and the harness
-keeps serving.
+how it gets there. A hive that hasn't been given the queue's address for its
+agents sets none of the four and each agent logs that it has none; a half-set
+environment logs an error and the harness keeps serving.
 
 ### Swarm-wide forge webhooks
 

docs/swarm/secrets.md

@@ -180,7 +180,7 @@ reads them out of its own `$CREDENTIALS_DIRECTORY`, owned by the agent user
 and by nobody else. `hive-c0re` never reads the bytes at any point: it runs as
 `hive-core`, which is the reason a copy wasn't an option either. When the
 files aren't there the daemon forwards nothing and says so in its journal, and
-the harness logs that it has no queue — the same absent-and-legal state, twice,
+the harness logs that it has no queue coordinates — the same absent-and-legal state, twice,
 rather than a container that refuses to start.
 
 ⚠️ **Service↔store mTLS is its own trust domain.** A credential you must

hive-agent/src/swarm_queue.rs

@@ -61,7 +61,7 @@ impl QueueEnv {
 enum Resolution {
     /// Everything is here; the agent can reach the queue.
     Configured(Box<QueueConfig>),
-    /// No queue for this agent, and that is a legal state — carries why.
+    /// No queue coordinates for this agent, and that is a legal state — carries why.
     Absent(&'static str),
     /// Some of the environment, not all of it. A deployment bug rather than
     /// an absent integration, so it is reported and then survived.
@@ -141,7 +141,7 @@ pub fn init() {
             Some(*cfg)
         }
         Resolution::Absent(why) => {
-            tracing::info!(why, "no swarm queue for this agent");
+            tracing::info!(why, "no swarm queue coordinates for this agent");
             None
         }
         Resolution::Partial => {
@@ -219,9 +219,10 @@ mod tests {
         );
     }
 
-    /// A hive with no swarm queue at all. Silence here is correct, and it has
-    /// to be distinguishable from the half-set case below — that distinction
-    /// is the only thing that makes the error branch worth logging.
+    /// A hive that has not been given its queue's coordinates at all. Silence
+    /// here is correct, and it has to be distinguishable from the half-set
+    /// case below — that distinction is the only thing that makes the error
+    /// branch worth logging.
     #[test]
     fn an_empty_environment_is_no_queue_rather_than_an_error() {
         let e = env([None, None, None, None]);

hive-c0re/src/lifecycle/host_config.rs

@@ -133,8 +133,8 @@ fn bind_child_agent_dirs(child: &str, binds: &mut Vec<BindMount>) {
 /// Env var naming the host directory `swarm-bao-queue-agent.service` lands
 /// this hive's agent queue credential in. Set by the hive-c0re NixOS module
 /// from `deploy.hive-controller.queue.agentCredentialDir`; absent means this
-/// daemon runs outside its unit, which is the same "no queue" answer as an
-/// empty directory.
+/// daemon runs outside its unit, which is the same "no queue credential"
+/// answer as an empty directory.
 const QUEUE_CREDENTIAL_DIR_ENV: &str = "HIVE_C0RE_AGENT_QUEUE_CREDENTIAL_DIR";
 
 /// systemd credential ids the two files arrive under inside the container.
@@ -167,7 +167,7 @@ fn queue_agent_credentials(agent_name: &str, dir: Option<&Path>) -> Vec<Credenti
     let Some(dir) = dir else {
         tracing::info!(
             %agent_name,
-            "no {QUEUE_CREDENTIAL_DIR_ENV} in this daemon's environment — agent gets no swarm queue"
+            "no {QUEUE_CREDENTIAL_DIR_ENV} in this daemon's environment — agent gets no swarm queue credential"
         );
         return Vec::new();
     };
@@ -179,7 +179,7 @@ fn queue_agent_credentials(agent_name: &str, dir: Option<&Path>) -> Vec<Credenti
     if !secret.is_file() || !client_id.is_file() {
         tracing::info!(
             %agent_name, dir = %dir.display(),
-            "swarm queue credential not published yet — agent gets no swarm queue"
+            "swarm queue credential not published yet — agent gets no swarm queue credential"
         );
         return Vec::new();
     }

hive-c0re/src/meta.rs

@@ -732,7 +732,7 @@ const FORWARDED_VARS: &[&str] = &[
 const FORWARDED_VAR_OPTIONS: &[(&str, &str)] = &[
     // Read at build time to decide whether the harness unit declares the
     // queue credential at all — see `nix/agent-modules/queue.nix`. An agent
-    // whose option says no queue and whose env says otherwise logs the
+    // whose option says no queue coordinates and whose env says otherwise logs the
     // partial-config error rather than half-connecting, which is the same
     // failure this map's doc describes and the reason both halves are wired.
     ("HIVE_AGENT_NATS_URL", "hyperhive.queue.natsUrl"),

nix/agent-modules/queue.nix

@@ -38,10 +38,10 @@ in
         which is the bridge address rather than a loopback one — inside this
         container `127.0.0.1` is the agent itself.
 
-        `null` means this hive has no queue, and the harness then declares no
-        credential and logs that it has none. It is deliberately not defaulted
-        to anything: a guessed address builds fine and talks to the wrong
-        machine.
+        `null` means this hive has not been given the queue's address for its
+        agents, and the harness then declares no credential and logs that it
+        has none. It is deliberately not defaulted to anything: a guessed
+        address builds fine and talks to the wrong machine.
       '';
     };
 
@@ -56,7 +56,7 @@ in
 
         Set together with {option}`hyperhive.queue.natsUrl` or not at all —
         the harness treats a half-set pair as a deployment bug rather than as
-        "no queue".
+        "no queue coordinates".
       '';
     };
   };

nix/host-modules/swarm.nix

@@ -611,7 +611,8 @@ in
       interface alone. ⚠️ Never a loopback address — inside an agent's network
       namespace `127.0.0.1` is the agent, not this host.
 
-      Null means this hive's agents have no queue. Together with
+      Null means this hive's agents have not been given the queue's address.
+      Together with
       {option}`services.hyperhive.swarm.statusPublish.tokenEndpoint` it is
       what decides whether the harness is handed queue coordinates at all; a
       hive whose queue is elsewhere names the address its containers route to.

nix/module-eval.nix

@@ -1278,7 +1278,8 @@ let
     }
     {
       # The agents mint against the swarm's IdP, the same endpoint the hive's
-      # own client uses — a hive-local guess would be a token no queue accepts.
+      # own client uses — a hive-local guess would produce a token the queue
+      # would not accept.
       name = "the agents' token endpoint is the swarm IdP's";
       ok =
         let
@@ -1289,8 +1290,9 @@ let
     }
     {
       # The absence arm, and what makes the two above able to fail: a hive
-      # with no queue must forward neither coordinate, because half a pair
-      # reaches the harness as a partial configuration rather than as none.
+      # with no queue address must forward neither coordinate, because half a
+      # pair reaches the harness as a partial configuration rather than as
+      # none.
       name = "a hive with no swarm queue forwards no agent queue coordinates";
       ok =
         let
@@ -1321,9 +1323,10 @@ let
         && e.HIVE_AGENT_OIDC_CLIENT_ID_FILE == "%d/hive-queue-agent-client-id";
     }
     {
-      # An agent built before its hive had a queue. It must declare nothing
-      # rather than name a credential that never arrives — and the harness
-      # then reports "no queue" instead of a half-set environment.
+      # An agent built before its hive was handed the queue's address. It
+      # must declare nothing rather than name a credential that never
+      # arrives — and the harness then reports "no queue coordinates"
+      # instead of a half-set environment.
       name = "an agent with no queue coordinates declares no credential";
       ok =
         let