fix(ui): distinguish root files in sidebar

[BowlOfSoup]

Summary

• Label each run of repository-root files with an in-place ./ sidebar header.
• Preserve the existing VCS or agent-provided review order.
• Keep root files visually distinct from the preceding folder group.

Closes #461

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[greptile-apps]

PR author is not in the allowed authors list.

[benvinegar]

Thanks for tackling #461 — I reproduced the ambiguity and agree that root files need a clearer boundary.

We tried an alternative that keeps the original VCS or agent-provided review order intact: emit a synthetic ./ group header whenever the ordered sidebar stream enters a run of repo-root files.

nested/
 M file.ts
./
 M zzz-root.ts

This makes the root transition explicit without hoisting files or changing the main review stream and navigation order. We have a small working patch with helper and rendered-component coverage.

Since maintainer edits are enabled, I’m happy to push the follow-up onto this branch, or you can adapt the PR yourself if you prefer. Would you be comfortable pivoting #519 to this presentation?

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[BowlOfSoup]

Since maintainer edits are enabled, I’m happy to push the follow-up onto this branch

Sure, go ahead. A few questions about the alternate proposal:

• Does it mean that indentation is always happening, for all directories and the root ./? On split screen terminals this might lead to space issues.
• The navigation order: why is it important to keep the VCS order, and not e.g. an alphabetical order?
• The proposed navigation order: does it mean that the list is scattered with ./ if there are lots of root directory changes? Hoisting (and alphabetically, but I didn't to that either) would give a better overview imo.

[benvinegar]

Does it mean that indentation is always happening, for all directories and the root ./? On split screen terminals this might lead to space issues.

The indentation accommodates the (M)odified indicator and the active file indicator. It's always there.

The navigation order: why is it important to keep the VCS order, and not e.g. an alphabetical order?

Because we're just trying to do the default thing everyone is used to.

does it mean that the list is scattered with ./ if there are lots of root directory changes?

There would just be one?

[benvinegar]

Thank you!