Fix metrics docs (#897)

### Description of change

##### Checklist

- [ ] Tested in playground or other setup
- [x] Documentation is changed or added
- [ ] Tests and/or benchmarks are included
- [ ] Breaking changes

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docs/content/concepts/flow-control/flow-label.md

@@ -97,9 +97,9 @@ high-cardinality label is detected, some of its values may be replaced with
 
 #### Default labels
 
-These are protocol-level labels (e.g. http, network) extracted by the
-configurated service mesh/middleware and are available to be referenced in
-[Selectors][selector], execept for a few high-cardinality ones.
+These are protocol-level labels (e.g. http, network) extracted by the configured
+service mesh/middleware and are available to be referenced in
+[Selectors][selector], except for a few high-cardinality ones.
 
 #### Labels extracted from baggage
 
@@ -113,8 +113,8 @@ SDK][aperture-go].
 
 :::note
 
-In the case of a clash, the Flow Label generated from the source takes
-predendence over the source below it:
+In the case of a clash, the Flow Label will be applied in the following
+precedence over:
 
 1. User-defined
 2. Baggage

docs/content/references/prometheus-metrics/_category_.yaml

@@ -0,0 +1,8 @@
+label: Prometheus Metrics
+position: 3
+collapsible: true
+collapsed: true
+link:
+  type: "generated-index"
+  title: "Prometheus Metrics"
+  keywords: ["prometheus", "metrics"]

docs/content/references/metrics/agent.md → docs/content/references/prometheus-metrics/agent.md

@@ -4,6 +4,8 @@ sidebar_position: 2
 sidebar_label: Agent
 ---
 
+Prometheus metrics generated by Aperture Agents.
+
 ## FluxMeter
 
 ### Metrics

docs/content/references/metrics/common.md → docs/content/references/prometheus-metrics/common.md

@@ -4,6 +4,8 @@ sidebar_position: 1
 sidebar_label: System
 ---
 
+Prometheus metrics generated by both, Aperture Agents and Aperture Controller.
+
 ## Go Metrics
 
 Go process metrics can be exposed by enabling `enable_go_metrics` flag in

docs/content/references/metrics/controller.md → docs/content/references/prometheus-metrics/controller.md

@@ -4,6 +4,8 @@ sidebar_position: 3
 sidebar_label: Controller
 ---
 
+Prometheus metrics generated by Aperture Controller.
+
 ## Signal
 
 ### Metrics