Codex Desktop: support VS Code-compatible file icon themes in the workspace file tree

What variant of Codex are you using?

App

What feature would you like to see?

Ask: Let users install/select third-party file icon themes for the workspace file tree (same job as VS Code “File Icon Theme”).

Examples users already have: Flow Icons, Material Icon Theme, vscode-icons, Symbols.

Why: Codex’s file tree already shows file-type icons, but only a small builtin set. People who live in Cursor/VS Code with a chosen icon pack lose that visual language in Codex, so file scanning is slower and the app feels less “their IDE.”

Desirable product shape (minimal):

1. Settings → Appearance (or Files): File icon theme picker (Builtin + installed themes).
2. Accept a VS Code-compatible icon theme package (the usual contributes.iconThemes JSON + SVG/iconPath maps: fileExtensions, fileNames, folderNames, light/dark).
3. Apply to workspace file-tree rows (files first; folder glyphs nice-to-have if it doesn’t fight expand chevrons).
4. Persist per-user; survive app updates without patching the app bundle.

Implementation hint for maintainers/agents: the desktop FileTree already has an icons config surface (spriteSheet, byFileName, byFileExtension, remap, builtin set: complete|standard|minimal|none). Official support can feed that API from an imported theme instead of growing the hardcoded builtin sprite forever. Full VS Code extension host is not required for v1.

Non-goals for v1: running arbitrary extension JS; marketplace inside Codex; restyling the whole app (see theming FR below).

Additional information

Related but different:

• #33497 — theme packs / stylesheets (colors & décor), not file-type icons
• #25448 / #19367 — per-project icons in the sidebar
• #24244 — file-tree panel UX, not icon packs

Agent-readable summary: feature-request codex-desktop file-tree file-icon-theme vscode-compatible user-value: visual parity with Cursor/VS Code icon packs.