Automatic Port Selection and Secured Communication (#1038)

Adds dynamic OS-selected socket port handling and secured Electron/.NET communication.

The dotnet-first startup flow now generates the auth token on the .NET side and passes it to Electron through an environment variable. Electron reports the selected socket port through a temporary startup-info file, avoiding any dependency on parsing Electron console output.

Also avoids logging backend startup parameters because they include the auth token.

src/ElectronNET.Host/api/browserWindows.js

@@ -277,7 +277,15 @@ module.exports = (socket, app) => {
             }
         });
         if (loadUrl) {
-            window.loadURL(loadUrl);
+            // Append authentication token to initial URL if available
+            const token = global["authToken"];
+            if (token) {
+                const separator = loadUrl.includes("?") ? "&" : "?";
+                window.loadURL(`${loadUrl}${separator}token=${token}`);
+            }
+            else {
+                window.loadURL(loadUrl);
+            }
         }
         if (app.commandLine.hasSwitch("clear-cache") &&
             app.commandLine.getSwitchValue("clear-cache")) {