[BUG] File viewer panel does not syntax-highlight PHP files (v2.1.199, Windows)

Description

In the File viewer panel, PHP source files are rendered as plain monochrome text with no syntax highlighting. Line numbers and the file-path header render correctly, but keywords / strings / comments get no coloring.

Environment

• Claude Code version: 2.1.199 (latest)
• OS: Windows 11 Pro (10.0.26200)
• Component: File viewer panel (desktop app)

Steps to reproduce

1. Open a session in a repo containing PHP files.
2. Open a .php file (e.g. app/Http/Controllers/Api/Client/OrderController.php) in the File viewer panel.
3. Observe the code shows without syntax highlighting.

Expected

PHP source is syntax-highlighted, same as other languages.

Actual

PHP file content is plain monochrome; no keyword/string/comment coloring. (Screenshot to be attached.)

Notes

• Reproduces on the latest version (2.1.199); updating did not help.
• Searched existing issues — no duplicate found for PHP file-viewer highlighting.