R-621: the hold panel points at the log the hold kept

A held app's page now says, inside the hold panel, that the app's own log from
before it was stopped was kept, with a Napló link to the logs page that serves
it (0b93e1a). Shown only for an update hold with a non-empty kept log
(Manager.HoldLogKept). New copy through the bundle (hu + en), parity case
app_info_hold_log captured when born.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/internal/web/templates/app_info.html

@@ -33,7 +33,7 @@
 {{else if and .Stack.HoldReason (eq .Stack.HoldKind "unhealthy_stop")}}
 <div class="alert alert-warning" style="margin-top:1rem" data-unhealthy-stop="true">{{holdText .Stack}}</div>
 {{else if .Stack.HoldReason}}
-<div class="alert alert-error" style="margin-top:1rem" data-held="true">{{holdText .Stack}}{{if not .Stack.HoldNoWholeCopy}} <a href="/backups/apps" class="btn btn-sm btn-outline">{{T "app_info.mentesek"}}</a>{{end}}</div>
+<div class="alert alert-error" style="margin-top:1rem" data-held="true">{{holdText .Stack}}{{if not .Stack.HoldNoWholeCopy}} <a href="/backups/apps" class="btn btn-sm btn-outline">{{T "app_info.mentesek"}}</a>{{end}}{{if .HoldLogKept}}<br><span data-hold-log="true">{{T "app_info.hold_log_kept"}}</span> <a href="/stacks/{{.Stack.Name}}/logs" class="btn btn-sm btn-outline">{{T "app_info.naplo"}}</a>{{end}}</div>
 {{else if .Stack.UpdateError}}
 <div class="alert alert-warning" style="margin-top:1rem" data-update-error="true">{{updateErrorText .Stack}}</div>
 {{else if .UpdateUndoneLine}}