assistant: Report all worktree entries in /file completions (#15617)
Piotr Osiewicz
created
We were reporting file count as worktree entry count, which led to us
missing some of the entries in /file command completion.
/cc @bennetbo
The other components that used `PathMatchCandidateSet` are
`/diagnostics` and file finder. File finder is unaffected, as it used
`Candidates::Files` - thus previously reported count was correct for it;
`/diagnostics` were using `::Entries` as well, so it could miss entries
just like `/files`.
Release Notes:
- Fixed /file and /diagnostics slash commands omitting entries in it's
completions menu.