chore: restores use-case readme (#137)

restore removed use-case/example scenario summary


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Author: iru

use-cases/README.md

@@ -0,0 +1,51 @@
+# Secure for Cloud for AWS Use-Cases
+
+
+
+Current examples were developed for simple use-case scenarios. 
+
+New use-cases are appearing and once we consolidate an standard scenario, we will create new examples to accommodate new requirements.
+
+Check [current use-case list](https://github.com/sysdiglabs/terraform-aws-secure-for-cloud/tree/master/use-cases), or use the [questionnaire](./_questionnaire.md) to let us know your needs
+
+
+
+## Use-Case summary
+
+### Examples
+
+|                   | `/examples/single-*`                                               | `/examples/organizational-*` |
+| --| -- | -- |
+| Deployment Type   | all Sysdig resources will be deployed within the selected account | Most Sysdig resources will be deployed within the selected account (just one), but some features, require resources to be deployed on all of the member-accounts (for Compliance and Image Scanning) . <br />One role is needed on the management account for cloudtrail event access |
+| Target          | will only analyse current account                                 |  handles all accounts (managed and member)|
+| Drawbacks         | cannot re-use another account Cloudtrail data (unless its deployed on the same account where the sns/s3 bucket is) | for scanning, a per-member-account access role is required |
+| More Info | [single-ecs](https://github.com/sysdiglabs/terraform-aws-secure-for-cloud/tree/master/examples/single-account-ecs), [single-apprunner](https://github.com/sysdiglabs/terraform-aws-secure-for-cloud/tree/master/examples/single-account-apprunner), [single-k8s](https://github.com/sysdiglabs/terraform-aws-secure-for-cloud/tree/master/examples/single-account-k8s) | [organizational](https://github.com/sysdiglabs/terraform-aws-secure-for-cloud/tree/master/examples/organizational) |
+
+With both examples `single` and `org`, you can customize the desired features to de deployed with the `deploy_*` input vars to avoid deploying more than wanted.
+
+
+<br/>
+
+### Compute Workload Type
+
+| Cloud | Example Options |
+| - | - |
+| AWS | K8S `-k8s`, ECS `-ecs`, AppRunner `-apprunner` |
+| GCP | K8S `-k8s`, CloudRun |
+| Azure | K8S `-k8s`, AzureContainerInstances |
+
+<br/><br/>
+
+
+## Available Optionals
+
+Make use of optionals to allow the re-use of pre-existing resources, and avoid incurring in more costs.
+
+|  Cloud |  Optionals | Related Input Vars | Other |
+| -- | --| -- | -- |
+| AWS  | Cloudtrail | single: [`cloudtrail_sns_arn`](https://github.com/sysdiglabs/terraform-aws-secure-for-cloud/tree/master/examples/single-account-ecs#input_cloudtrail_sns_arn)<br/>organizational: [`existing_cloudtrail_config`](https://github.com/sysdiglabs/terraform-aws-secure-for-cloud/tree/master/examples/organizational#input_existing_cloudtrail_config) | - |
+| | ECS, VPC, Subnet | `ecs_cluster_name`, `ecs_vpc_id`, `ecs_vpc_subnets_private_ids` | if used, the three are mandatory  |
+| GCP | - | - | - |
+| Azure | ResourceGroup | `resource_group_name` | - |
+| | ACR | `registry_name`, `registry_resource_group_name` | - |
+| * | Compute Workload | - | All clouds allow Sysdig Secure for cloud to be deployed on a pre-existing K8S cluster|