Refactor project to modularize constants and utilities.

Moved reusable constants and helper functions to dedicated modules for improved maintainability and reusability. Improved build configuration to differentiate output directories for development and production. Enhanced server error handling and added safeguards for disabled web UI scenarios.

app/server.go

@@ -208,6 +208,15 @@ func (s *Server) UserInterface() {
 					origDirector(req)
 					req.Host = target.Host
 				}
+				// Suppress noisy "context canceled" errors from browser navigation
+				s.devProxy.ErrorHandler = func(w http.ResponseWriter, r *http.Request, err error) {
+					if r.Context().Err() == context.Canceled {
+						// Browser canceled the request - this is normal, don't log it
+						return
+					}
+					log.Printf("proxy error: %v", err)
+					http.Error(w, "Bad Gateway", http.StatusBadGateway)
+				}
 			}
 		}
 	}
@@ -282,6 +291,12 @@ func (s *Server) handleFavicon(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// If web UI is disabled without a proxy, return 404
+	if s.Config != nil && s.Config.WebDisableEmbedded {
+		http.NotFound(w, r)
+		return
+	}
+
 	// Serve orly-favicon.png as favicon.ico from embedded web app
 	w.Header().Set("Content-Type", "image/png")
 	w.Header().Set("Cache-Control", "public, max-age=86400") // Cache for 1 day
@@ -302,6 +317,12 @@ func (s *Server) handleLoginInterface(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// If web UI is disabled without a proxy, return 404
+	if s.Config != nil && s.Config.WebDisableEmbedded {
+		http.NotFound(w, r)
+		return
+	}
+
 	// Serve embedded web interface
 	ServeEmbeddedWeb(w, r)
 }