Bump Grafana Alloy to v1.14.0 (#292)

## Summary
- Bump alloy-k8s, alloy-ringtail, and alloy-tracing-ringtail image tags from v1.13.1 to v1.14.0
- Mark indri alloy (ansible) as reviewed at v1.14.0 — source rebuild from forge mirror needed
- Add missing alloy-ringtail entry to service-versions.yaml
- Update alloy reference doc

## Breaking changes reviewed
- `loki.secretfilter` options removed — not used in our configs
- OTel Collector upgraded to v0.142.0 — Kafka receiver changes don't affect us
- Exporter queue default changes — our tracing pipeline (Beyla → batch → otlphttp) uses simple config, low risk

## Deployment and Testing
- [ ] Sync alloy-k8s: `argocd app set alloy-k8s --revision bump/alloy-v1.14.0 && argocd app sync alloy-k8s`
- [ ] Sync alloy-ringtail: `argocd app set alloy-ringtail --revision bump/alloy-v1.14.0 --server ringtail-argocd && argocd app sync alloy-ringtail`
- [ ] Sync alloy-tracing-ringtail similarly
- [ ] Verify metrics flowing in Grafana
- [ ] Verify traces flowing to Tempo (ringtail)
- [ ] Rebuild indri alloy from source (`v1.14.0` tag on forge mirror), SCP to indri, restart
- [ ] After merge: reset ArgoCD revisions to main, re-sync

Reviewed-on: #292

argocd/manifests/alloy-k8s/kustomization.yaml

@@ -10,7 +10,7 @@ resources:
 
 images:
   - name: grafana/alloy
-    newTag: v1.13.1
+    newTag: v1.14.0
 
 configMapGenerator:
   - name: alloy-config

argocd/manifests/alloy-ringtail/kustomization.yaml

@@ -10,7 +10,7 @@ resources:
 
 images:
   - name: grafana/alloy
-    newTag: v1.13.1
+    newTag: v1.14.0
 
 configMapGenerator:
   - name: alloy-config

argocd/manifests/alloy-tracing-ringtail/kustomization.yaml

@@ -9,7 +9,7 @@ resources:
 
 images:
   - name: grafana/alloy
-    newTag: v1.13.1
+    newTag: v1.14.0
 
 configMapGenerator:
   - name: alloy-tracing-config