grafana dashboards: shorten panel descriptions

Cut every panel/board description down to a short statement of what the
number is. Drops the design-reasoning prose, edge-case notes, and
operator-attributed quotes that had accumulated in an earlier pass —
useful context while building the boards, wrong shape for a tooltip an
operator glances at mid-incident.

nix/host-modules/swarm-grafana/dashboards/queue.json

@@ -1,7 +1,7 @@
 {
   "title": "hyperhive · queue (nats)",
   "uid": "hyperhive-swarm-queue",
-  "description": "NATS / JetStream health for the swarm queue. Split out of the combined swarm-services board: a page whose content is really N services should be N pages.",
+  "description": "The swarm's NATS/JetStream queue.",
   "editable": true,
   "refresh": "1m",
   "schemaVersion": 39,
@@ -17,7 +17,7 @@
       "id": 1,
       "type": "stat",
       "title": "Queue connections",
-      "description": "Clients currently attached to the swarm's NATS server. Zero is NOT healthy here: hive-c0re's status publisher, swarm-controller and the notices stream all hold a connection, so an empty count means the queue is refusing everyone rather than being idle. A callout denial reaches a client as a timeout, so this panel is often the first place that failure is visible at all. No `or vector(0)`, deliberately: that fallback belongs on counts-of-failures, and here it would render a missing exporter as zero clients — conflating a dead queue with a dead scrape, which the scrape panels above already answer.",
+      "description": "Clients currently connected to the queue.",
       "datasource": {
         "type": "prometheus",
         "uid": "@datasourceUid@"
@@ -80,7 +80,7 @@
       "id": 2,
       "type": "stat",
       "title": "Queue subscriptions",
-      "description": "Active subscriptions across all connected clients. Read alongside the connection count: connections steady while subscriptions collapse means clients are attached but no longer listening, which a liveness check cannot see.",
+      "description": "Active subscriptions across all clients.",
       "datasource": {
         "type": "prometheus",
         "uid": "@datasourceUid@"
@@ -139,7 +139,7 @@
       "id": 3,
       "type": "stat",
       "title": "Slow consumers",
-      "description": "Clients the server has disconnected for failing to keep up. Healthy value is zero, so this panel reads empty when everything is fine — see the queue-connections panel for whether the server is being talked to at all.",
+      "description": "Clients disconnected for falling behind.",
       "datasource": {
         "type": "prometheus",
         "uid": "@datasourceUid@"
@@ -203,7 +203,7 @@
       "id": 4,
       "type": "stat",
       "title": "JetStream API errors",
-      "description": "Errors answering JetStream API requests. The KV bucket the hive status publisher writes to lives behind this API, so a non-zero value here explains a status page that has gone stale without anything else looking wrong.",
+      "description": "Errors answering JetStream API requests.",
       "datasource": {
         "type": "prometheus",
         "uid": "@datasourceUid@"
@@ -267,7 +267,7 @@
       "id": 5,
       "type": "timeseries",
       "title": "Queue messages (range)",
-      "description": "Messages in and out over the selected range. Deliberately `increase()` rather than a per-second rate: this queue carries a status publish per hive per interval and little else, so a rate divides a handful of messages across an hour and draws a flat zero.",
+      "description": "Messages sent and received in the selected range.",
       "datasource": {
         "type": "prometheus",
         "uid": "@datasourceUid@"
@@ -333,7 +333,7 @@
       "id": 6,
       "type": "stat",
       "title": "Pending bytes to clients",
-      "description": "Bytes queued for delivery to clients. Rises BEFORE a slow consumer is counted, so this is the leading indicator for the panel beside it. Zero is the healthy value.",
+      "description": "Bytes queued for delivery to clients.",
       "datasource": {
         "type": "prometheus",
         "uid": "@datasourceUid@"
@@ -391,7 +391,7 @@
       "id": 7,
       "type": "timeseries",
       "title": "JetStream store size vs limit",
-      "description": "The only capacity question the queue has. Used and configured limit on one axis so the headroom is legible without arithmetic; a stream that grows unboundedly shows up here first.",
+      "description": "Store size used against its configured limit.",
       "datasource": {
         "type": "prometheus",
         "uid": "@datasourceUid@"