Feature: Show "failed to read" title indication for the current folder as well as the global one

Right now, if we fail to read files (eg. because we got a "permission denied" error), we only show their count globally. It would be great if we could also in addition show them for the current folder (if there are any).

Start by tracing the Rust CLI code that renders the current folder title and handles failed-to-read counts. Confirm how the global count is calculated, then make the current folder show its own count when applicable while preserving the global indication; done means both scopes display correctly for readable and unreadable folders.

Written by the indexing model from the issue text.