Add a note about Serverless architectures + small fixes

Author: vishaangelova

manage-data/ingest/ingest-reference-architectures.md

@@ -19,6 +19,10 @@ To ingest data into {{es}}, use the *simplest option that meets your needs* and
 You can host {{es}} on your own hardware or send your data to {{es}} on {{ecloud}}. For most users, {{agent}} writing directly to {{es}} on {{ecloud}} provides the easiest and fastest time to value. {{ech}} is available on {{aws}}, GCP, and Azure, and you can [try it for free](https://cloud.elastic.co/registration).
 ::::
 
+::::{admonition} Elastic Cloud Serverless architectural differences
+The architecture diagrams below show {{es}} and {{kib}} as separate components. In {{serverless-full}}, they are combined into a single integrated architecture: {{es-serverless}}.
+::::
+
 **Decision tree**
 
 [Data ingestion](../ingest.md)

reference/fleet/example-kubernetes-fleet-managed-agent-helm.md

@@ -2,7 +2,7 @@
 mapped_pages:
   - https://www.elastic.co/guide/en/fleet/current/example-kubernetes-fleet-managed-agent-helm.html
 applies_to:
-  stack: ga 8.18
+  stack: ga
   serverless: ga
 products:
   - id: fleet

reference/fleet/example-kubernetes-standalone-agent-helm.md

@@ -2,7 +2,7 @@
 mapped_pages:
   - https://www.elastic.co/guide/en/fleet/current/example-kubernetes-standalone-agent-helm.html
 applies_to:
-  stack: ga 8.18
+  stack: ga
   serverless: ga
 products:
   - id: fleet

reference/fleet/migrate-elastic-agent.md

@@ -53,7 +53,7 @@ You can create a new cluster based on the snapshot taken in the previous step, a
 
 ## Update settings in the target cluster [migrate-elastic-agent-target-settings]
 
-when the target cluster is available you’ll need to adjust a few settings. Take some time to examine the {{fleet}} setup in the new cluster.
+When the target cluster is available you’ll need to adjust a few settings. Take some time to examine the {{fleet}} setup in the new cluster.
 
 1. Open the {{kib}} menu and select **Fleet**.
 2. On the **Agents** tab, your agents should visible, however they’ll appear as `Offline`. This is because these agents have not yet enrolled in the new, target cluster, and are still enrolled in the original, source cluster.