fix/promql rules review 2 (#534)

* fix(data): fix queries and thresholds across multiple exporters

- Ceph: fix OSD latency metric name (ceph_osd_apply_latency_ms), replace
  ceph_osd_utilization with ceph_health_detail{name="OSD_NEARFULL"}, add for: durations
- ZFS: improve description, remove incorrect ON() join on readonly check
- Thanos: filter gRPC errors to actual error codes only (drop NotFound, Cancelled, etc.)
- Loki/Promtail: fix histogram_quantile to aggregate by (namespace, job, route, le)
- Mimir: raise rate()>0 thresholds to >0.05, add missing for: durations
- OTel Collector: raise rate()>0 thresholds to >0.05, add deprecation comments
- Tempo/Cortex: raise >0 thresholds to avoid transient spikes
- APC UPS: add division-by-zero guard on battery voltage ratio
- DigitalOcean: raise increase()>0 to >3
- Grafana Alloy: fix missing name: field on exporter
- Graph Node: add threshold comments

* fix(data): remove official mixin reference from Ceph OSD comment

* fix(data): remove official mixin references from comments

_data/rules.yml

@@ -4551,7 +4551,7 @@ groups:
                 for: 1m
                 comments: |
                   ceph_health_status: 0=HEALTH_OK, 1=HEALTH_WARN, 2=HEALTH_ERR.
-                  This rule fires on any non-OK state. Split into separate warning/critical rules by using ==1 and ==2 thresholds if needed.
+                  This rule fires on any non-OK state. Split into ==1 (warning) and ==2 (critical) if you want separate severity levels.
               - name: Ceph monitor clock skew
                 description: Ceph monitor clock skew detected. Please check ntp and hardware clock settings
                 query: "abs(ceph_monitor_clock_skew_seconds) > 0.2"
@@ -4581,7 +4581,7 @@ groups:
                 for: 5m
                 comments: |
                   Ceph internally triggers OSD_NEARFULL based on the nearfull_ratio (default 85%).
-                  ceph_health_detail can also be used for more granular OSD space alerts.
+                  ceph_health_detail exposes named health checks as individual time series.
               - name: Ceph OSD reweighted
                 description: Ceph Object Storage Daemon takes too much time to resize.
                 query: "ceph_osd_weight < 1"