[Bug]: "@" file search returns no results when the query contains "[" (dynamic route folders like [id]) #34465

Before submitting#

• I searched existing issues and did not find a duplicate.
• I included enough detail to reproduce or investigate the problem.

Area#

apps/web

Steps to reproduce#

1. Open a project that has a path with a bracketed folder, for example an Expo Router or Next.js dynamic route: src/app/game/[id]/index.tsx
2. In the composer, type @game/index. The picker lists index.tsx under src/app/game/[id].
3. Clear the composer and type @game/[i or @game/[id].

Expected behavior#

The picker lists the files and folders whose path contains game/[id], such as src/app/game/[id]/index.tsx. The search treats "[" and "]" as literal characters.

Actual behavior#

The picker shows "No matching files or folders." as soon as the query contains "[". The same file appears when the query leaves out the bracketed segment (@game/index), so the file is indexed. Only the bracket query fails.

Parentheses work: @(modals) matches route group folders like (modals). Only "[" and "]" fail.

Still reproduces with Settings → Chat → Rich text composer turned off, so this is not the markdown rewrite from #16413.

Impact#

Minor bug or occasional failure

Version or commit#

Version 0.1.8 (bf469bb19669)

Environment#

macOS 27.2 (26B123), T3 Code desktop app

Screenshots, recordings, or supporting files#

Dynamic Route no match:

Skip dynamic route in search matches:

Workaround#

Search without the bracketed segment, for example @game/index, then pick the file from the list.