fix: resolve nlreturn, modernize, perfsprint, wsl_v5, and partial err113 lint issues

internal/server/routes.go

@@ -71,16 +71,20 @@ func (s *Server) SetupRoutes() {
 		s.log.Error("failed to get web dist filesystem", "error", err)
 	} else {
 		fileServer := http.FileServer(http.FS(distFS))
+
 		s.router.Get("/*", func(w http.ResponseWriter, r *http.Request) {
 			// Try to serve the file; if not found, serve index.html for SPA routing
 			f, err := distFS.(fs.ReadFileFS).ReadFile(r.URL.Path[1:])
 			if err != nil || len(f) == 0 {
 				indexHTML, _ := distFS.(fs.ReadFileFS).ReadFile("index.html")
+
 				w.Header().Set("Content-Type", "text/html; charset=utf-8")
 				w.WriteHeader(http.StatusOK)
 				_, _ = w.Write(indexHTML)
+
 				return
 			}
+
 			fileServer.ServeHTTP(w, r)
 		})
 	}