docs(i18n): update LOLcat (x-lolcat) README to new structure (#289)

Rewrite x-lolcat README to match ja/en structure while preserving
the LOLcat-specific opening and closing sections.
Changes:
- Rewrite full body from ja/ template, translated to LOLcat
- Add Profile Management UI section
- Add SSH Key Management / IdentitiesOnly explanation
- Improve Quick Start guide (first-ux image support)
- Expand Troubleshooting section
- Fix image paths (ja/ -> x-lolcat/)
- Fix language flags (bold cat emoji, JP flag links to ../ja/)
- Keep sample profiles from Log-0007 (Ceiling Cat theme)
- 3 rounds of self-review improvements

🖥️ IDE: [Cursor](https://cursor.sh)
🔌 Extension: [Claude Code](https://claude.ai/download)


Model-Raw: claude-opus-4-6

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: nullvariant