docs(c4): fix 3d frontend — add User actor for /hilfe/transkription

The help guide is used by all transcribers, not just administrators. Only
showing admin as the actor was misleading about who accesses this route.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/architecture/c4-diagrams.md

@@ -471,6 +471,7 @@ C4Component
     title Component Diagram: Web Frontend — Administration & Help
 
     Person(admin, "Administrator")
+    Person(user, "User")
     Container(backend, "API Backend", "Spring Boot")
 
     System_Boundary(frontend, "Web Frontend (SvelteKit / SSR)") {
@@ -483,6 +484,7 @@ C4Component
     }
 
     Rel(admin, adminUsers, "Manages users and invites", "HTTPS / Browser")
+    Rel(user, hilfe, "Views transcription style guide", "HTTPS / Browser")
     Rel(adminUsers, backend, "GET/POST/DELETE /api/users, POST /api/auth/invite", "HTTP / JSON")
     Rel(adminGroups, backend, "GET/POST/PUT/DELETE /api/groups", "HTTP / JSON")
     Rel(adminTags, backend, "GET/PUT/DELETE /api/tags", "HTTP / JSON")