doc: Document deleting and restoring entities (#1182)

* doc: Document deleting and restoring entities

* fixup! doc: Document deleting and restoring entities

* fixup! doc: Document deleting and restoring entities

doc/content/the-things-stack/management/purge/_index.md

@@ -1,16 +1,99 @@
 ---
-title: "Purging Entities"
+title: "Deleting, Restoring and Purging Entities"
 description: ""
 weight:
 aliases: [/reference/purge]
 ---
 
-When entities are deleted, {{% tts %}} [retains some IDs]({{< ref "reference/id-eui-constraints" >}}) by default to prevent another user re-registering the ID and obtaining historical data.
+When entities are deleted, {{% tts %}} [retains some IDs]({{< ref "reference/id-eui-constraints" >}}) by default to prevent another user re-registering the ID and obtaining historical data. Deleted entities can be restored within a limited time period, but it is also possible for administrators to purge these entities, so that their IDs may be reused.
 
-It is also possible for administrators to purge IDs so that they may be reused. This reference contains information about how to do this, and the implications of purging IDs.
+This reference contains information about how to do delete, restore and purge entities.
 
 <!--more-->
 
+{{< note >}} End devices cannot be soft deleted, i.e. once they are deleted, they cannot be restored anymore. Hence, information below regarding restoring and manual purging refers to other entities - applications, gateways, clients, users and organizations. {{</ note >}}
+
+## Deleting and Restoring Entities
+
+{{< tabs/container "Console" "CLI" >}}
+
+{{< tabs/tab "Console" >}}
+
+Go to the **General Settings** tab of the entity and click **Delete**.
+
+{{< figure src="delete.png" >}}
+
+If you are an administrator, you will also be presented with the option to purge the entity. For implications of purging entities and other details, check [sections below]({{< relref "#what-happens-to-purged-entities" >}}).
+
+{{</ tabs/tab >}}
+
+{{< tabs/tab "CLI" >}}
+
+To delete an end device (keep in mind the note above!):
+
+```bash
+ttn-lw-cli applications delete --application-id <application-id> --device-id <device-id>
+```
+
+To delete an application:
+
+```bash
+ttn-lw-cli applications delete --application-id <application-id>
+```
+
+To delete a client:
+
+```bash
+ttn-lw-cli clients delete --client-id <client-id>
+```
+
+To delete a gateway:
+
+```bash
+# By EUI
+ttn-lw-cli gateways delete --gateway-eui <gateway-eui>
+# Or by ID
+ttn-lw-cli gateways delete --gateway-id <gateway-id>
+```
+
+To delete an organization:
+
+```bash
+ttn-lw-cli organizations delete --organization-id <organization-id>
+```
+
+To delete a user:
+
+```bash
+ttn-lw-cli users delete --user-id <user-id>
+```
+
+{{</ tabs/tab >}}
+
+{{</ tabs/container >}}
+
+When entities are deleted, there is a default time period of 24h when an administrator can restore them. For {{% tts %}} Enterprise deployments, it is possible to configure this restoration period. For more info, check [Identity Server Options]({{< ref "/reference/configuration/identity-server#general-options" >}}).
+
+Note again that restoring entities is not possible if they have been purged.
+
+{{< tabs/container "Console" "CLI" >}}
+
+{{< tabs/tab "Console" >}}
+
+To restore an entity using the Console, navigate to the **Deleted (Admin)** tab for the entity of interest, and click **Restore**.
+
+{{< figure src="restore-app.png" >}}
+
+{{< /tabs/tab >}}
+
+{{< tabs/tab "CLI" >}}
+
+To restore an entity using the CLI, just replace `delete` with `restore` in commands presented above.
+
+{{< /tabs/tab >}}
+
+{{< /tabs/container >}}
+
 ## What Happens to Purged Entities?
 
 Only administrators may purge entities. Purging an entity has the following effects:
@@ -37,24 +120,17 @@ Purging entities using the Console or the CLI is usually most convenient, so tho
 
 {{< tabs/tab "Console" >}}
 
-Go to the **General Settings** tab of the entity and click **Delete**.
-
-{{< figure src="delete.png" >}}
-
-If you are an administrator, you will be presented with the option to purge the entity. Check the **Also release entity IDs** box to also purge the entity.
+There are two ways to purge an entity:
+- Go to the **General Settings** tab of the entity and click **Delete**. If you are an administrator, you will be presented with the option to purge the entity. Check the **Also release entity IDs** box to also purge the entity.
 
 {{< figure src="purge.png" >}}
 
+- After soft-deleting the entity with **Delete**, navigate to the **Deleted (Admin)** panel (the same panel where you restore entities), find your deleted entity and click **Purge**.
+
 {{</ tabs/tab >}}
 
 {{< tabs/tab "CLI" >}}
 
-To view soft-deleted users:
-
-```bash
-ttn-lw-cli user list --deleted --all
-```
-
 To purge an application:
 
 ```bash