perf(render): viewport culling, live POIs, external TraCI attach

Rendering
- Spatially index lanes; cull lane/vehicle/POI buffers to visible world
  bounds with pan headroom. Rebuild only when scale crosses a 3% LOD
  step or the viewport leaves the cached region.
- Coalesce pan deltas onto a 60 Hz timer so trackpad/scroll events
  don't thrash GPU buffers.
- Cap zoom at a per-network maximum derived from lane widths so small
  networks can't blow past the lane-width cap.
- Skip vehicle interpolation (and drop to 30 Hz) for dense fleets where
  animation isn't visible anyway.

Selection & contrast
- Draw selected lanes/junctions as alpha overlays on top of the base
  color instead of replacing it, so selection no longer masks state.
- Add WCAG-aware stroke/detail colors for vehicle icons.

Live POIs
- Poll "slot_*" POIs each tick via new poiPosition/poiColor TraCI calls
  and surface them through SimulationState.pois alongside static POIs.

External TraCI attach
- Add --traci-port / --traci-order launch flags and a 60×500ms connect
  retry budget so an external runner can spawn SUMO and have
  SumoMacGUI attach.

SumoLauncher
- Extract SumoLauncher.arguments and switch to bare --no-step-log /
  --no-warnings; update CHECKLIST note.

Tests
- NetworkRenderLODTests, ViewportStateTests, new SumoLauncherTests
  cover the helpers above.

Author: christofilojohn

Sources/SumoGUIMac/App/LaunchConfiguration.swift

@@ -2,18 +2,30 @@ import Foundation
 
 struct LaunchConfiguration: Equatable {
     let openURL: URL?
+    let traciPort: Int?
+    let traciClientOrder: Int32
 
     static func from(arguments: [String], currentDirectoryURL: URL = URL(fileURLWithPath: FileManager.default.currentDirectoryPath)) -> LaunchConfiguration {
         let args = Array(arguments.dropFirst())
         var iterator = args.makeIterator()
         var openPath: String?
+        var traciPort: Int?
+        var traciClientOrder: Int32 = 2
 
         while let arg = iterator.next() {
             switch arg {
             case "-c", "--config":
                 if let next = iterator.next(), isSupportedInputPath(next) {
                     openPath = next
                 }
+            case "--traci-port":
+                if let next = iterator.next(), let port = Int(next), (1...65_535).contains(port) {
+                    traciPort = port
+                }
+            case "--traci-order":
+                if let next = iterator.next(), let order = Int32(next) {
+                    traciClientOrder = order
+                }
             case let path where !path.hasPrefix("-") && openPath == nil && isSupportedInputPath(path):
                 openPath = path
             default:
@@ -22,11 +34,11 @@ struct LaunchConfiguration: Equatable {
         }
 
         guard let openPath else {
-            return LaunchConfiguration(openURL: nil)
+            return LaunchConfiguration(openURL: nil, traciPort: traciPort, traciClientOrder: traciClientOrder)
         }
 
         let url = URL(fileURLWithPath: openPath, relativeTo: currentDirectoryURL).standardizedFileURL
-        return LaunchConfiguration(openURL: url)
+        return LaunchConfiguration(openURL: url, traciPort: traciPort, traciClientOrder: traciClientOrder)
     }
 
     private static func isSupportedInputPath(_ path: String) -> Bool {

Sources/SumoGUIMac/App/SumoGUIMacApp.swift

@@ -7,7 +7,11 @@ struct SumoGUIMacApp: App {
 
     init() {
         let launchConfiguration = LaunchConfiguration.from(arguments: CommandLine.arguments)
-        _simulation = StateObject(wrappedValue: SimulationViewModel(initialOpenURL: launchConfiguration.openURL))
+        _simulation = StateObject(wrappedValue: SimulationViewModel(
+            initialOpenURL: launchConfiguration.openURL,
+            initialTraciPort: launchConfiguration.traciPort,
+            initialTraciClientOrder: launchConfiguration.traciClientOrder
+        ))
     }
 
     var body: some Scene {