docs: add new sensors and buttons

Author: jcwillox

docs/assets/example-sensors-extra.png

@@ -1,3 +1,26 @@
-The built-in sensor can be used to monitor the status of your backups.
+# Entities
+
+Entities for monitoring and controlling the Auto Backup integration.
+
+![example-sensors.png](assets/example-sensors.png)
+
+| Name              | Type            | Enabled by default | Description                                                                                                  |
+| ----------------- | --------------- | ------------------ | ------------------------------------------------------------------------------------------------------------ |
+| Purge             | `button`        | ✅                 | Purge expired backups ondemand, otherwise, they are purged automatically when creating a new backup          |
+| Backup Status     | `binary_sensor` | ✅                 | Displays whether a backup operation is currently running                                                     |
+| Successful        | `binary_sensor` |                    | Whether the last backup **succeeded** or **failed**                                                          |
+| Last Failure      | `sensor`        | ✅                 | Time of the last **failed** backup                                                                           |
+| Last Success      | `sensor`        | ✅                 | Time of the last **successful** backup                                                                       |
+| Monitored backups | `sensor`        | ✅                 | How many backups have an expiry date and are being monitored to be purged.                                   |
+| Purgeable backups | `sensor`        | ✅                 | The number of backups which have passed their expiry date and will be purged during the next purge operation |
+| Next Expiration   | `sensor`        |                    | How long until the next non-expired backup will expire                                                       |
+
+---
+
+**Additional images**
+
+![example-sensors-extra.png](assets/example-sensors-extra.png)
+
+![example-sensors-list.png](assets/example-sensors-list.png)
 
 ![Sensor Example](assets/example-sensor.png)

docs/assets/example-sensors-list.png

@@ -19,8 +19,8 @@ extra:
 nav:
   - "index.md"
   - "services.md"
-  - "events.md"
   - "sensors.md"
+  - "events.md"
   - "faq.md"
   - Examples:
       - "examples.md"