[BUG] FileIndex re-indexes large non-git codebase via ripgrep causing multi-second hitches every turn

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Working with Claude Code on a large project (200k+ files), but without a git repo (we use P4). I'm seeing multi-second hitches every turn as Claude re-indexes files. On my machine this is currently taking between 7-13 seconds every turn, on a slower machine in the office here it takes 20+ seconds.

When there is a git repo, Claude reindexes once at the start of the session and then never again. I've been able to confirm this as a workaround by creating a local git repo, and after all of the files are committed, the hitch no longer occurs (confirmed times by looking at debug logs).

If I use an .ignore or .rgignore, I can reduce the number of files that ripgrep tests, but the re-indexing is still occurring every turn.

What Should Happen?

For non-git repos there should be some kind of file index cache for the and not re-scan files every turn.

Error Messages/Logs

[FileIndex] getProjectFiles called, respectGitignore=true
  [FileIndex] getFilesUsingGit called
  [FileIndex] not a git repo, returning null
  [FileIndex] git ls-files returned null, falling back to ripgrep
  [FileIndex] ripgrep: 204372 files in 12842ms
  [FileIndex] cache refresh completed in 13049ms

Steps to Reproduce

1. In a project with hundreds of thousands of files (ours has ~230k), open Claude Code. Do not create a git repo at that location (or above it in the file path)
2. Note that Claude Code hitches on startup, and every turn afterwards

Claude Model

Not sure / Multiple models

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.96

Platform

AWS Bedrock

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

[FileIndex] getProjectFiles called, respectGitignore=true
[FileIndex] getFilesUsingGit called
[FileIndex] not a git repo, returning null
[FileIndex] git ls-files returned null, falling back to ripgrep
[FileIndex] ripgrep: 211764 files in 6758ms
[FileIndex] cache refresh completed in 6992ms

[FileIndex] getProjectFiles called, respectGitignore=true
[FileIndex] not a git repo, returning null
[FileIndex] git ls-files returned null, falling back to ripgrep
[FileIndex] ripgrep: 203599 files in 6654ms
[FileIndex] cache refresh completed in 6890ms

[FileIndex] getProjectFiles called, respectGitignore=true
[FileIndex] not a git repo, returning null
[FileIndex] git ls-files returned null, falling back to ripgrep
[FileIndex] ripgrep: 202984 files in 6619ms
[FileIndex] cache refresh completed in 6853ms

[FileIndex] getProjectFiles called, respectGitignore=true
[FileIndex] not a git repo, returning null
[FileIndex] git ls-files returned null, falling back to ripgrep
[FileIndex] ripgrep: 208870 files in 6762ms
[FileIndex] cache refresh completed in 6987ms

[FileIndex] getProjectFiles called, respectGitignore=true
[FileIndex] not a git repo, returning null
[FileIndex] git ls-files returned null, falling back to ripgrep
[FileIndex] ripgrep: 201247 files in 7306ms
[FileIndex] cache refresh completed in 7537ms