fix(login): Language selector is not working due to httponly cookie

[belcirelk]

The login page is set to the default browser language, but it's impossible to change the language using the select a the bottom of the login page. The page reload back the previous language.
The readCookie('language') returns null, the reason is that the cookie is set as HTTPonly and can not be read by javascript. The solution is to read the cookie via the tpl instead.

closes #747

[Copilot]

Pull Request Overview

This PR fixes a language selector issue on the login page where users cannot change the language due to an HTTPOnly cookie that cannot be read by JavaScript. The fix replaces JavaScript cookie reading with server-side template variable access.

• Replaces client-side cookie reading with server-side Smarty template variable
• Enables proper language selector functionality on the login page
• Resolves issue where page would reload to previous language instead of selected language

[JohnVillalovos]

I just tried this and I'm not seeing a difference. I tried to use "Espanol" as the language and don't notice any difference.

This is after I selected "Espanol" It still shows "English US" and content is English.

[JohnVillalovos]

One thing I am noticing on my test instance is that this is the cookie set:

{
	"Response Cookies": {
		"language": {
			"expires": "2025-08-23T15:56:33.000Z",
			"httpOnly": true,
			"path": "/Web",
			"samesite": "Lax",
			"secure": true,
			"value": "es"
		}
	}
}

I am NOT using HTTPS on my test instance and here we can see that secure: true. Will need to figure out how to make the language cookie to be allowed to not be secure.

[belcirelk]

Yes, the way it's done currently it will only work over HTTPS.

[JohnVillalovos]

LGTM. I have a follow on fix for the cookie to change it to not be required to be HTTPS.