feat: speed test through the browser, client - panel - browser (0.0.6)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/server/handlers_panel.go

@@ -185,6 +185,7 @@ func (s *Server) handleAgentDelete(w http.ResponseWriter, r *http.Request) {
 	}
 	_ = s.db.DeleteAgent(id)
 	s.stats.drop(id)
+	s.relays.drop(id, nil)
 	s.hub.Forget(id)
 	http.Redirect(w, r, "/", http.StatusSeeOther)
 }