fix: use file basename when moving buffer + file

`cj/--move-buffer-and-file` was building the destination as `(concat dir "/" (buffer-name))`. If the buffer had been renamed via `M-x rename-buffer`, or uniquified by Emacs with a `<2>` suffix when a second buffer visited the same filename, the move wrote a file with the wrong name on disk.

I derived the destination basename from `buffer-file-name` instead, in both the internal helper and the interactive wrapper. The wrapper's overwrite-prompt now also formats the real target filename rather than the buffer name.

I added two regression tests: one for a renamed buffer visiting `original.txt`, and one for a `<2>` uniquified buffer with a trailing-slash target directory.

0 files changed, 0 insertions, 0 deletions