fix(elasticsan): resolve Go SDK breaking changes by moving restoreVolume to Management client (Azure#35969)

- Add @clientLocation decorator to move restoreVolume operation to Management client for Go
- This maintains backward compatibility for existing Go SDK consumers
- Resolves 3 breaking changes identified during TypeSpec migration:
  * ClientFactory.NewManagementClient removal
  * NewManagementClient removal
  * ManagementClient.BeginRestoreVolume removal
- Follows Pattern 4 (Client Organization Changes) from breaking changes guide

Author: tadelesh

specification/elasticsan/ElasticSan.Management/client.tsp

@@ -67,3 +67,6 @@ using Azure.Core;
 @@clientName(PrivateLinkResource, "ElasticSanPrivateLinkResource", "csharp");
 @@usage(PrivateLinkResource, Usage.input, "csharp");
 @@clientName(restoreVolume, "RestoreVolume", "csharp");
+
+// Move restoreVolume operation to Management client for Go to maintain compatibility
+@@clientLocation(Microsoft.ElasticSan.restoreVolume, "Management", "go");