expose 'storage_type' on the sys/seal-status endpoint (#7486)

* expose 'storage_type' on the sys/seal-status endpoint

* add comments

* Update vault/core.go

Co-Authored-By: Brian Kassouf <briankassouf@users.noreply.github.com>

command/server.go

@@ -664,6 +664,7 @@ func (c *ServerCommand) Run(args []string) int {
 	coreConfig := &vault.CoreConfig{
 		Physical:                  backend,
 		RedirectAddr:              config.Storage.RedirectAddr,
+		StorageType:               config.Storage.Type,
 		HAPhysical:                nil,
 		Seal:                      barrierSeal,
 		AuditBackends:             c.AuditBackends,