docs(devel/ote): added devel docs for OTE CCM-AWS

Creating development document to build and use the OTE binary for
CCM-AWS project.

Author: mtulio

docs/dev/ote-ccm-aws.md

@@ -0,0 +1,92 @@
+# OpenShift Tests Extension (OTE) for AWS Cloud Controller Manager
+
+The OpenShift Tests Extension (OTE) binary `aws-cloud-controller-manager-tests-ext`
+exposes the upstream e2e tests from `cloud-provider-aws` (implemented under `tests/e2e`)
+to the OpenShift test framework. Tests are selected/curated by the filters defined in
+`main.go`, so that only the intended subset is available in the OpenShift test pipeline.
+
+OpenShift-specific (downstream) tests live under `cmd/cloud-controller-manager-aws-tests-ext/e2e`
+and are added to the list of tests executed by `openshift-tests`.
+
+The OTE library uses dot imports to register both upstream and downstream Ginkgo specs into the suite.
+
+```mermaid
+flowchart LR
+    A["Upstream Tests<br/>kubernetes/cloud-provider-aws<br/>tests/e2e"] --> C["OTE Binary<br/>aws-cloud-controller-manager-tests-ext"]
+    B["Downstream Tests<br/>openshift/cluster-cloud-controller-manager-operator<br/>cmd/cloud-controller-manager-aws-tests-ext/e2e"] --> C
+    C --> D["openshift-tests<br/>execution framework"]
+
+    style A fill:#e1f5ff
+    style B fill:#fff4e1
+    style C fill:#e8f5e9
+    style D fill:#f3e5f5
+```
+
+## Directory Structure
+
+```
+cmd/cloud-controller-manager-aws-tests-ext/
+├── e2e/
+│   ├── loadbalancer.go    # OpenShift-specific load balancer tests
+│   └── helper.go           # Helper functions (AWS clients, feature gate checks, etc.)
+├── main.go                 # Test binary entrypoint
+└── README.md
+```
+
+## Prerequisites
+
+- Go 1.24+
+- Access to an OpenShift cluster on AWS
+- Valid `KUBECONFIG` pointing to the cluster
+- AWS credentials configured (for tests that query AWS APIs)
+
+## Building
+
+### Building the test binary
+
+To build the OTE binary from the root of the project:
+
+```sh
+make cloud-controller-manager-aws-tests-ext
+```
+
+The binary will be created at the `bin/` directory: `./bin/cloud-controller-manager-aws-tests-ext`.
+
+### Building the container image
+
+To build the container image (regular CCCMO build):
+
+```sh
+make image
+```
+
+The binary will be created in the container image path `/usr/bin/cloud-controller-manager-aws-tests-ext.gz`.
+
+## Using the test binary
+
+### List available tests
+
+```sh
+./aws-cloud-controller-manager-tests-ext list --topology=HighAvailability --platform=aws | jq .[].name
+```
+
+Example output:
+```
+"[cloud-provider-aws-e2e-openshift] loadbalancer NLB feature AWSServiceLBNetworkSecurityGroup should have NLBSecurityGroupMode = Managed in cloud-config [Suite:openshift/conformance/parallel]"
+...
+"[cloud-provider-aws-e2e] nodes should set zone-id topology label [Suite:openshift/conformance/parallel]"
+"[cloud-provider-aws-e2e] nodes should label nodes with topology network info if instance is supported [Suite:openshift/conformance/parallel]"
+```
+
+### List test suites
+
+```sh
+./bin/cloud-controller-manager-aws-tests-ext list suites | jq .[].name
+```
+
+### Run a specific test
+
+```sh
+export KUBECONFIG=/path/to/kubeconfig
+./bin/cloud-controller-manager-aws-tests-ext run-test "[cloud-provider-aws-e2e-openshift] loadbalancer NLB [OCPFeatureGate:AWSServiceLBNetworkSecurityGroup] should have security groups attached to default ingress controller NLB [Suite:openshift/conformance/parallel]"
+```