[fix/3505] Chinese character rendering problem

[mitre88]

Problem

Chinese characters do not render correctly on first display. After any button press, they display correctly.

Root Cause

On Linux/FreeBSD, the cosmic_text FontSystem was initialized with a hardcoded 'en' locale. The locale is used by cosmic_text to determine which fallback fonts to use for non-Latin characters like CJK.

Fix

Read the LANG environment variable at TextLayoutSystem initialization and use it to configure the FontSystem locale. This ensures CJK characters display correctly on first render.

Fixes #3505

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[oz-for-oss]

@mitre88

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[oz-for-oss]

Overview

This PR changes the winit text layout font system initialization to derive the cosmic-text locale from LANG instead of hardcoding en.

Concerns

• The new code uses a cosmic_text::Locale API, but the locked cosmic-text API takes a String locale for FontSystem::new_with_locale_and_db, so this hunk will not compile as written.

Verdict

Found: 1 critical, 0 important, 0 suggestions

Request changes

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[oz-for-oss]

🚨 [CRITICAL] This does not type-check with the locked cosmic-text API: FontSystem::new_with_locale_and_db expects a String, and cosmic_text::Locale is not part of that API. Keep this as a String and normalize the POSIX LANG value before passing it through.

Suggested change

	let locale = std::env::var("LANG")
	.ok()
	.filter(|lang| !lang.is_empty())
	.map(cosmic_text::Locale::new)
	.unwrap_or_else(|| cosmic_text::Locale::new("en").expect("en is a valid locale"));
	let locale = std::env::var("LANG")
	.ok()
	.and_then(|lang| lang.split('.').next().map(str::to_string))
	.filter(|lang| !lang.is_empty())
	.map(|lang| lang.replace('_', "-"))
	.unwrap_or_else(|| "en".to_string());

[mitre88]

Closing this to keep my open PR queue focused on contributions that are currently reviewable and likely to proceed. This one has a blocking signal (changes-requested-cla) and would need a deeper rework before it is worth maintainer time. Thanks for the review/context.