fix(dir): keep a listing buffer when the initial listing fails

Problem:  A failed initial directory listing discards the listing state:
          the user is left in an empty modifiable non-listing buffer, and
          the BufEnter autocmd retries the failing open, repeating the
          error on every re-entry.
Solution: Render the failure as an empty listing with state and handlers
          intact: the error is reported once and "R" or :edit retries the
          listing. Keep the error on the listing state so a failed
          listing is distinguishable from an empty one; the next list
          clears it.

0 files changed, 0 insertions, 0 deletions