[DOCS] Add Observability topic (elastic#73041) (elastic#74334)

* Add observability content

* Remove xpack from file name

* Updates following review

* Review edits

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>

docs/observability/index.asciidoc

@@ -0,0 +1,24 @@
+[chapter]
+[role="xpack"]
+[[observability]]
+= Observability
+
+Observability enables you to add and monitor your logs, system
+metrics, uptime data, and application traces, as a single stack. 
+
+With *Observability*, you have:
+
+* A central place to add and configure your data sources.
+* A variety of charts displaying analytics relating to each data source.
+* *View in app* options to drill down and analyze data in the Logs, Metrics, Uptime, and APM apps.
+* An alerts chart to keep you informed of any issues that you may need to resolve quickly.
+
+[role="screenshot"]
+image::observability/images/observability-overview.png[Observability Overview in {kib}]
+
+[float]
+== Get started
+
+{kib} provides step-by-step instructions to help you add and configure your data
+sources. The {observability-guide}/index.html[Observability Guide] is a good source for more detailed information
+and instructions.

docs/user/index.asciidoc

@@ -27,6 +27,8 @@ include::graph/index.asciidoc[]
 
 include::visualize.asciidoc[]
 
+include::{kib-repo-dir}/observability/index.asciidoc[]
+
 include::{kib-repo-dir}/logs/index.asciidoc[]
 
 include::{kib-repo-dir}/infrastructure/index.asciidoc[]