Document diff backup functionality

Author: jackwaudby

modules/ROOT/pages/clustering/databases.adoc

@@ -468,7 +468,7 @@ SHOW DATABASE foo;
 === Seed from URI
 
 This method seeds all servers with an identical seed from an external source, specified by the URI.
-The seed can be either a backup or a dump from an existing database.
+The seed can either be a full backup, a differential backup (xref:clustering/databases.adoc#cloud-seed-provider[`CloudSeedProvider`] only), or dump from an existing database. 
 The sources of seeds are called _seed providers_.
 
 The mechanism is pluggable, allowing new sources of seeds to be supported (see link:https://www.neo4j.com/docs/java-reference/current/extending-neo4j/project-setup/#extending-neo4j-plugin-seed-provider[Java Reference -> Implement custom seed providers] for more information).
@@ -527,6 +527,9 @@ label:new[Introduced in 5.25], the `CloudSeedProvider` supports:
 ** `gs:` 
 ** `azb:`
 
+The `CloudSeedProvider` also supports xref:backup-restore/modes.adoc#differential-backup[differential backup] files as seeds.
+When a differential backup file is provided the `CloudSeedProvider` tries to find in the differential backup file's folder a xref:backup-restore/online-backup.adoc#backup-chain[backup chain] ending at the specified differential backup, then seeds using this backup chain.
+
 [.tabbed-example]
 =====
 [role=include-with-AWS-S3 label--new-5.25]