Storage: Add mode 2 dual writing improvements (#87204)

* Fix mode 2 List test
* Set origin timestamp during conversion to k8s resource
* Add instructions for updating a playlist
* Handle partial deletions of a collection in mode 2

pkg/services/store/entity/README.md

@@ -100,6 +100,9 @@ metadata:
   generateName: x # anything is ok here... except yes or true -- they become boolean!
   labels:
     foo: bar
+  annotations:
+    grafana.app/slug: "slugger"
+    grafana.app/updatedBy: "updater"
 spec:
   title: Playlist with auto generated UID
   interval: 5m
@@ -129,6 +132,13 @@ NAME                                   TITLE                              INTERV
 u394j4d3-s63j-2d74-g8hf-958773jtybf2   Playlist with auto generated UID   5m         2023-12-14T13:53:35Z 
 ```
 
+To update the playlist, update the `playlist-generate.yaml` file then run:
+```sh
+kubectl --kubeconfig=./grafana.kubeconfig patch playlist <NAME> --patch-file playlist-generate.yaml
+```
+
+In the example, `<NAME>` would be `u394j4d3-s63j-2d74-g8hf-958773jtybf2`.
+
 ### Use a separate database
 
 By default Unified Storage uses the Grafana database. To run against a separate database, update `custom.ini` by adding the following section to it: