Add CODEOWNERS and README

Description:
- Add instructions on how to run the controller locally
- Add `CODEOWNERS` to ensure only the [GOV.UK Platform Engineering team](https://github.com/orgs/alphagov/teams/gov-uk-platform-engineering) can approve
- alphagov/govuk-infrastructure#4172

Author: nimalank7

.github/CODEOWNERS

@@ -0,0 +1,2 @@
+# Platform Engineering review required
+* @alphagov/gov-uk-platform-engineering

.github/workflows/test-chart.yml

@@ -0,0 +1,78 @@
+name: Test Chart
+
+on:
+  push:
+  pull_request:
+
+permissions: {}
+
+jobs:
+  test-e2e:
+    permissions:
+      contents: read
+    name: Run on Ubuntu
+    runs-on: ubuntu-latest
+    env:
+      IMG: controller:latest
+    steps:
+      - name: Clone the code
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+
+      - name: Setup Go
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
+        with:
+          go-version-file: go.mod
+
+      - name: Install the latest version of kind
+        run: |
+          curl -Lo ./kind https://kind.sigs.k8s.io/dl/latest/kind-linux-$(go env GOARCH)
+          chmod +x ./kind
+          sudo mv ./kind /usr/local/bin/kind
+
+      - name: Verify kind installation
+        run: kind version
+
+      - name: Create kind cluster
+        run: kind create cluster
+
+      - name: Prepare govuk-job-request-operator
+        run: |
+          go mod tidy
+          make docker-build
+          kind load docker-image $IMG
+
+      - name: Install Helm
+        run: make install-helm
+
+      - name: Lint Helm Chart
+        run: |
+          helm lint ./dist/chart
+
+# TODO: Uncomment if cert-manager is enabled
+#      - name: Install cert-manager via Helm (wait for readiness)
+#        run: |
+#          helm repo add jetstack https://charts.jetstack.io
+#          helm repo update
+#          helm install cert-manager jetstack/cert-manager \
+#            --namespace cert-manager \
+#            --create-namespace \
+#            --set crds.enabled=true \
+#            --wait \
+#            --timeout 300s
+
+# TODO: Uncomment if Prometheus is enabled
+#      - name: Install Prometheus Operator CRDs
+#        run: |
+#          helm repo add prometheus-community https://prometheus-community.github.io/helm-charts
+#          helm repo update
+#          helm install prometheus-crds prometheus-community/prometheus-operator-crds
+
+      - name: Deploy manager via Helm
+        run: |
+          make helm-deploy
+
+      - name: Check Helm release status
+        run: |
+          make helm-status

README.md

@@ -1,14 +1,104 @@
 # GOV.UK Job Request Operator
 
-This is a k8s operator that is used to make job requests built with [operator-sdk](https://sdk.operatorframework.io/).
+This is a k8s operator that is used to make job requests built with [kube-builder](https://github.com/kubernetes-sigs/kubebuilder).
 
 ## Usage
 
-To install the required dependencies::
+To install the required dependencies:
 
 ```shell
-brew install operator-sdk
+brew install kubebuilder
 brew install helm
+brew install k3d
+```
+
+### Custom Resource Definition (CRD)
+
+```
+apiVersion: platform.gov.uk/v1
+kind: JobRequest
+metadata:
+  labels:
+    app.kubernetes.io/name: govuk-job-request-operator
+    app.kubernetes.io/managed-by: kustomize
+  name: jobrequest-sample
+spec:
+  foo: bar
+```
+
+### Create and generate the manifests
+
+1. Create the manifests
+
+```
+make manifests
+```
+
+2. Start a k3d cluster
+
+```
+k3d cluster create cluster --api-port 6550
+```
+
+3. Install the CRDs into the cluster
+
+```
+make install
+```
+
+### Run the controller locally
+
+1. Run the controller locally
+
+This will run the controller locally and not in the cluster.
+
+```
+make run
+```
+
+2. Create a custom resource
+
+Edit `platform_v1_jobrequest.yaml` to the following:
+
+```
+spec:
+    foo: bar
+```
+
+3. Apply the resource
+
+```
+kubectl apply -k config/samples
+```
+
+### Run the controller in the cluster
+
+1. Build the controller in a docker image
+
+```
+make docker-build
+```
+
+2. Modify the `manager` manifest
+
+Edit the `manager` Deployment in `config/manager/manager.yaml` to include the following:
+
+```
+imagePullPolicy: IfNotPresent
+```
+
+3. Load the image into the cluster
+
+```
+k3d image import controller:latest -c cluster
+```
+
+### Generate Helm chart
+
+1. Generate a Helm chart
+
+```
+kubebuilder edit --plugins=helm/v2-alpha
 ```
 
 ## Team