Allow `custom_main.js` To Modify Command Line Switches

[AeonSake]

Currently, all proprietary command line switches are checked before the custom_main.js script can run, thus making it impossible to modify those specific switches.

Electron.NET/src/ElectronNET.Host/main.js

Lines 27 to 68 in 456135a

	if (app.commandLine.hasSwitch('manifest')) {
	manifestJsonFileName = app.commandLine.getSwitchValue('manifest');
	}
	console.log('Entry!!!: ');
	if (app.commandLine.hasSwitch('unpackedelectron')) {
	unpackedelectron = true;
	}
	else if (app.commandLine.hasSwitch('unpackeddotnet')) {
	unpackeddotnet = true;
	}
	else if (app.commandLine.hasSwitch('dotnetpacked')) {
	dotnetpacked = true;
	}
	if (app.commandLine.hasSwitch('electronforcedport')) {
	electronforcedport = app.commandLine.getSwitchValue('electronforcedport');
	}
	// Custom startup hook: look for custom_main.js and invoke its onStartup(host) if present.
	// If the hook returns false, abort Electron startup.
	try {
	const fs = require('fs');
	const customMainPath = path.join(__dirname, 'custom_main.js');
	if (fs.existsSync(customMainPath)) {
	const customMain = require(customMainPath);
	if (customMain && typeof customMain.onStartup === 'function') {
	const continueStartup = customMain.onStartup(globalThis);
	if (continueStartup === false) {
	////console.log('custom_main.js onStartup returned false. Exiting Electron host.');
	// Ensure the app terminates immediately before further initialization.
	// Use app.exit to allow Electron to perform its shutdown, fallback to process.exit.
	try { app.exit(0); } catch (err) { process.exit(0); }
	}
	} else {
	console.warn('custom_main.js found but no onStartup function exported.');
	}
	}
	} catch (err) {
	console.error('Error while executing custom_main.js:', err);
	}

It would be great, if the checks for the individual switches were moved below the custom_main.js handling, which would allow the script to potentially modify the command line switches. This change won't break any existing application but would allow users to, e.g., force a specific startup method (e.g., by also checking environment variables as shown in the wiki article).

On that note: there might be a better approach to force a startup method at compile-time, but this is currently the only realistic way to achieve this without requiring users to run the app with CLI arguments (or create shortcuts with CLI arguments), specifically .NET-first packaged execution.