Attempt to fix WiFi file transfer crash by adding initialization delay

Fixed a simple bug where WiFi file transfer would crash and lock the device when accessed directly. The issue was caused by missing initialization time after WiFi.mode(WIFI_STA) call,.

Root cause:
- Hotspot mode includes delay(100) after WiFi.mode(WIFI_AP) to allow hardware initialization
- Join Network mode was missing this delay after WiFi.mode(WIFI_STA)
- Without the delay, WiFi wasn't properly initialized
- This caused crashes when starting the web server in STA mode

Fix:
- Added delay(100) after WiFi.mode(WIFI_STA) in onNetworkModeSelected()
- Matches the proven initialization pattern used in hotspot mode
- Comment added to explain the purpose of the delay

src/activities/network/CrossPointWebServerActivity.cpp

@@ -138,7 +138,8 @@ void CrossPointWebServerActivity::onNetworkModeSelected(const NetworkMode mode)
     // STA mode - launch WiFi selection
     Serial.printf("[%lu] [WEBACT] Turning on WiFi (STA mode)...\n", millis());
     WiFi.mode(WIFI_STA);
-
+    delay(100);  // Allow WiFi hardware to initialize before proceeding
+    
     state = WebServerActivityState::WIFI_SELECTION;
     Serial.printf("[%lu] [WEBACT] Launching WifiSelectionActivity...\n", millis());
     enterNewActivity(new WifiSelectionActivity(renderer, mappedInput,