Website: Add polish translation, improve locale detection

[MaciejkaG]

This pull request improves the browser locale detection and adds Polish translations.

[Copilot]

Pull Request Overview

This PR adds Polish translation support to the website and improves the browser locale detection system by replacing a simple prefix check with a more comprehensive language mapping approach.

• Add complete Polish translations for all website strings
• Replace basic browser language detection with a configurable mapping system
• Update language selector to include Polish option

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
website/app/i18n/pl.ts	Adds complete Polish translation strings for the website
website/app/i18n/context.tsx	Improves locale detection logic and integrates Polish translations
website/app/components/LanguageSelector/LanguageSelector.tsx	Adds Polish language option to the selector

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[Copilot]

The Chinese variant detection logic is fragile. Using lang.includes("hant") will incorrectly match locales like 'zh-Hans-CN' (Simplified Chinese) as Traditional Chinese because 'Hans' contains 'hant'. Use a more precise check like lang.includes('zh-hant') or lang.includes('hk') || lang.includes('tw') for Traditional Chinese detection.

Suggested change

	zh: (lang) => lang.includes("hant") ? "zh-Hant" : "zh",
	zh: (lang) =>
	lang.includes("zh-hant") ||
	lang.includes("zh-hk") ||
	lang.includes("zh-tw") ||
	lang.endsWith("-hant") ||
	lang.endsWith("-hk") ||
	lang.endsWith("-tw")
	? "zh-Hant"
	: "zh",