Add Simplified Chinese (ZH) language support with CJK font fix across all pages

[Copilot]

The site only supported EN/DE. This adds ZH as a third locale across all pages, with localStorage-backed preference persistence, and fixes CJK glyph rendering that caused Chinese text to appear as white boxes.

Changes

• Language switcher — Added ZH button alongside EN/DE on index.html, impressum.html, and datenschutz.html
• Translations — Full zh translation object in index.html covering header, features, support form (placeholders, price estimates, discount codes), footer, changelog (年/月 date format), and reviews; equivalent content translated in impressum.html and datenschutz.html
• Persistence — Language choice written to localStorage; all pages read it on load so switching on one page persists site-wide
• CJK font rendering — Inter has no CJK glyphs; added Noto Sans SC to the Google Fonts request and inserted it into the font-family stack on all three pages, eliminating the white-box fallback

<!-- font import -->
<link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;600;700&family=Noto+Sans+SC:wght@400;600;700&display=swap" rel="stylesheet" />

font-family: "Inter", "Noto Sans SC", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;

Main page (ZH):

Impressum page (ZH):

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Project	Deployment	Actions	Updated (UTC)
project-x	Ready	Preview, Comment	Mar 2, 2026 11:24am

[theodorismmmm]

@copilot Also make the buttons work for the impressum and DATENSCHUTZ site

[Copilot]

@copilot Also make the buttons work for the impressum and DATENSCHUTZ site

Done in commit 46cead1. Both impressum.html and datenschutz.html now have the EN/DE/ZH language switcher with full translations. The language preference also persists across all pages via localStorage, so switching to ZH on one page keeps it on the others.

[devNull-bootloader]

@copilot Why does it look like white boxes in the screenshots? Btw how can I coauthor this PR? I wanna ge that achievement.

[Copilot]

@copilot Why does it look like white boxes in the screenshots? Btw how can I coauthor this PR? I wanna ge that achievement.

The white boxes appeared because Inter (the site's font) has no CJK glyphs — the browser couldn't render Chinese characters. Fixed in 9697251 by adding Noto Sans SC (Google's Simplified Chinese font) to the Google Fonts import and the font-family stack on all three pages. Chinese characters will now render properly everywhere.