[eltociear]

Summary

I created Japanese translated README.

• Added README.ja.md, a Japanese translation of README.en.md.
• Added a 日本語 entry to the language selector in README.md and README.en.md, and a 日本語 README link to the documentation index in docs/README.md.
• UI labels mentioned in the README use the app's own Japanese strings from src/App/Localization/Strings.ja-JP.xaml (e.g. ドライバー管理, ミラーリングを開始, Aデモ（推奨）).

Validation

• ./scripts/verify_localization.ps1
• ./build.ps1 -Configuration Release
• Core protocol tests pass
• GUI behavior checked when applicable
• User-facing documentation and release notes updated when behavior, ports, dependencies or output formats changed
• Real-device result includes ProductType/iOS but no UDID

Documentation-only change, so the build, localization and device checks above were not run (n/a). The new file was compared with README.en.md: same line count and paragraph line breaks, same Markdown structure, identical code blocks, inline code and links, and git diff --check is clean.

Risk review

• No real UDID, pairing record, user path, private screen content or raw USB capture is included
• No unbounded frame/audio queue or UI-thread USB work was introduced
• Driver, elevation and registry behavior is unchanged, or the change is clearly documented
• Protocol activation and stop behavior is unchanged, or tested on a real device
• Third-party binaries, hashes and license obligations are unchanged, or fully documented

UI evidence

n/a (no visual changes).

[RayrenSX]

Thank you @eltociear for contributing the Japanese README and adding the language links! I've reviewed the translation, checked the key UI labels against the Japanese localization resources, and verified the commands and repository links. Everything looks good. I've approved the workflow run and enabled auto-merge once the required build check passes. Thanks for making iPhoneMirror more accessible to Japanese-speaking users!