feat(prometheus, prometheus-operator): add support for automatic grafana datasources/dashboards (#16917)

**Description**
This PR aims to do two things:
1. It enabled automatic loading of grafana dashboards to the
prometheus-operator. Dashboards fetched directly from upstream
2. It enables automatic loading of Prometheus as grafana datasource

Why have the dashboards on the operator?
We use upstream operator helm-chart dependency, which already allows us
to use the latest dashboards from upstream. Without custom code, copying
etc.

Which limits the chance of mistakes/bugs.

**⚙️ Type of change**

- [x] ⚙️ Feature/App addition
- [ ] 🪛 Bugfix
- [ ] ⚠️ Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [ ] 🔃 Refactor of current code

**🧪 How Has This Been Tested?**
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**📃 Notes:**
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**✔️ Checklist:**

- [ ] ⚖️ My code follows the style guidelines of this project
- [ ] 👀 I have performed a self-review of my own code
- [ ] #️⃣ I have commented my code, particularly in hard-to-understand
areas
- [ ] 📄 I have made corresponding changes to the documentation
- [ ] ⚠️ My changes generate no new warnings
- [ ] 🧪 I have added tests to this description that prove my fix is
effective or that my feature works
- [ ] ⬆️ I increased versions for any altered app according to semantic
versioning

**➕ App addition**

If this PR is an app addition please make sure you have done the
following.

- [ ] 🪞 I have opened a PR on
[truecharts/containers](https://github.com/truecharts/containers) adding
the container to TrueCharts mirror repo.
- [ ] 🖼️ I have added an icon in the Chart's root directory called
`icon.png`

---

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charts/enterprise/prometheus/Chart.yaml

@@ -1,7 +1,7 @@
 kubeVersion: ">=1.24.0-0"
 apiVersion: v2
 name: prometheus
-version: 16.1.9
+version: 16.2.0
 appVersion: 2.48.1
 description: kube-prometheus-stack collects Kubernetes manifests, Grafana dashboards, and Prometheus rules combined with documentation and scripts to provide easy to operate end-to-end Kubernetes cluster monitoring with Prometheus using the Prometheus Operator.
 home: https://truecharts.org/charts/enterprise/prometheus

charts/enterprise/prometheus/questions.yaml

@@ -194,7 +194,7 @@ questions:
                             description: "This port exposes the container port on the service"
                             schema:
                               type: int
-                              default: 10086
+                              default: 9090
                               required: true
         - variable: alertmanager
           label: "alertmanager Service"
@@ -216,7 +216,7 @@ questions:
                             description: "This port exposes the container port on the service"
                             schema:
                               type: int
-                              default: 10087
+                              default: 9093
                               required: true
 # Include{serviceExpertRoot}
 # Include{serviceExpert}

charts/enterprise/prometheus/values.yaml

@@ -23,6 +23,36 @@ workload:
               enabled: false
             startup:
               enabled: false
+              
+
+configmap:
+  grafana-datasource:
+    enabled: "{{ if .Values.grafana.datasource.enabled }}true{{ else }}false{{ end }}"
+    data:
+      datasource.yaml: |-
+        apiVersion: 1
+        datasources:
+        - name: Prometheus
+          type: prometheus
+          uid: {{ .Values.grafana.datasource.uid | default "prometheus" }}
+          url: http://{{ include "tc.v1.common.lib.chart.names.fullname" $ }}.{{ include "tc.v1.common.lib.metadata.namespace" (dict "rootCtx" $ "objectData" . "caller" "Configmap") }}:{{ .Values.service.main.ports.main.port }}
+          access: proxy
+          isDefault: {{ .Values.grafana.datasource.default | default true }}
+          jsonData:
+            httpMethod: {{ .Values.grafana.datasource.httpMethod | default "POST" }}
+            timeInterval: {{ .Values.grafana.datasource.scrapeInterval | default "30s" }}
+            {{- if .Values.grafana.datasource.timeout }}
+            timeout: {{ .Values.grafana.datasource.timeout }}
+            {{- end }}
+
+grafana:
+  datasource:
+    enabled: true
+    default: true
+    httpMethod: "POST"
+    scrapeInterval: "30s"
+    uid: "prometheus"
+
 service:
   main:
     selectorLabels:
@@ -30,7 +60,7 @@ service:
       prometheus: '{{ template "kube-prometheus.prometheus.fullname" . }}'
     ports:
       main:
-        port: 10086
+        port: 9090
         targetPort: 9090
         protocol: http
   alertmanager:
@@ -41,7 +71,7 @@ service:
     ports:
       alertmanager:
         enabled: true
-        port: 10087
+        port: 9093
         targetPort: 9093
         protocol: http
   thanos:

charts/operators/prometheus-operator/Chart.yaml

@@ -1,7 +1,7 @@
 kubeVersion: ">=1.24.0-0"
 apiVersion: v2
 name: prometheus-operator
-version: 4.1.0
+version: 4.2.0
 appVersion: latest
 description: Prometheus Operator is an operator for prometheus
 home: https://truecharts.org/charts/operators/prometheus-operator

charts/operators/prometheus-operator/values.yaml

@@ -74,6 +74,7 @@ kps:
   ##
   grafana:
     enabled: false
+    forceDeployDashboards: true
 
   ## Flag to disable all the kubernetes component scrapers
   ##