Fix SSO clients page template wrapper

Page templates must define a named block that invokes {{template "base"}}
(e.g. {{define "sso_clients"}}{{template "base" .}}{{end}}). Without this,
ExecuteTemplate cannot find the named template and returns an error.

Also add logging to the SSO clients handler for easier diagnosis.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

web/templates/sso_clients.html

@@ -1,3 +1,4 @@
+{{define "sso_clients"}}{{template "base" .}}{{end}}
 {{define "title"}} - SSO Clients{{end}}
 {{define "content"}}
 <div class="page-header d-flex justify-between align-center">