Remove dev env var requirement and update docs for latest config (#10483)

* Update docs for alerts and event review

* Add docs for camera groups

* Update reference config with new config values

* Remove env variable requirement

* Add to sidebar

* Update snapshot docs

* add zones example to detection docs too

* Generalize the zone docs

docs/docs/configuration/reference.md

@@ -653,4 +653,19 @@ telemetry:
   # Optional: Enable the latest version outbound check (default: shown below)
   # NOTE: If you use the HomeAssistant integration, disabling this will prevent it from reporting new versions
   version_check: True
+
+# Optional: Camera groups (default: no groups are setup)
+# NOTE: It is recommended to use the UI to setup camera groups
+camera_groups:
+  # Required: Name of camera group
+  front:
+    # Required: list of cameras in the group
+    cameras:
+      - front_cam
+      - side_cam
+      - front_doorbell_cam
+    # Required: icon used for group
+    icon: car
+    # Required: index of this group
+    order: 0
 ```