Docs: updates for file-based menu (#28500)

* initial

* cleanup

* remove bad aliases

* cleanup, fix links

* add docs-file-based-command

* update docs

* update readme

* fix broken links

* fix spelling

Co-authored-by: Diana Payton <52059945+oddlittlebird@users.noreply.github.com>

docs/sources/dashboards/annotations.md

@@ -1,11 +1,7 @@
 +++
 title = "Annotations"
 keywords = ["grafana", "annotations", "documentation", "guide"]
-type = "docs"
 aliases = ["/docs/grafana/latest/reference/annotations/"]
-[menu.docs]
-name = "Annotations"
-parent = "dashboard_features"
 weight = 2
 +++