@file autocomplete adds incorrect ../ prefix in git subdirectories

Description

When running Claude Code from a subdirectory of a git repository, the @ file autocomplete incorrectly prepends ../ to file paths.

Steps to Reproduce

1. Have a git repo at /parent/
2. Run Claude Code from /parent/child/ subdirectory
3. Type @ and press tab to autocomplete a file in the current directory
4. File paths are suggested as @../filename instead of @filename

Expected Behavior

Files in the current working directory should be suggested as @filename, not @../filename

Actual Behavior

Files are suggested with ../ prefix as if they were in the parent directory

Environment

• OS: macOS (Darwin 25.2.0)
• Claude Code v2.0.76