Add link from Agent quickstart to data lifecycle (#3133)

This tiny PR adds a link at the bottom of "Quickstart: Monitor hosts
with Elastic Agent" to the data lifecycle docs:

<img width="605" height="142" alt="obs-ilm-link"
src="https://github.com/user-attachments/assets/89a2ba14-fbd3-4724-866d-9ec8a5f276e6"
/>

---

Closes: #1568

Please see preview: Quickstart: [Manage your
data](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/3133/solutions/observability/get-started/quickstart-monitor-hosts-with-elastic-agent#_manage_your_data)
(in "Monitor hosts with Elastic Agent")

Author: kilfoyle

solutions/observability/get-started/quickstart-monitor-hosts-with-elastic-agent.md

@@ -178,4 +178,8 @@ For host monitoring, the following capabilities and features are recommended:
     * [Detect change points](/explore-analyze/machine-learning/machine-learning-in-kibana/xpack-ml-aiops.md#change-point-detection) in your time series data.
 
 
-Refer to the [Observability overview](/solutions/observability/get-started/what-is-elastic-observability.md) for a description of other useful features.
+Refer to the [Observability overview](/solutions/observability/get-started/what-is-elastic-observability.md) for a description of other useful features.
+
+## Manage your data [_manage_your_data]
+
+Now that you're ingesting data and using it gather insights, learn how to manage your [data lifecycle](/manage-data/lifecycle.md). These features in {{es}} allow you to govern how long your {{agent}} data is retained, and to tune performance by configuring background operations that optimize how your data is stored.