* fix(daytona): quote single-upload mkdir parent path
The single-file _daytona_upload() path shelled out 'mkdir -p {parent}'
with the remote parent interpolated unquoted, so shell metacharacters in
the path could break the command or inject arbitrary commands into the
sandbox. The bulk-upload, bulk-download, and delete paths were already
hardened with shlex-quoting helpers; this single-upload path was missed.
Route it through the existing quoted_mkdir_command() helper and add a
regression test covering a path with shell metacharacters.
Reported by @Gutslabs (#3960); the original branch predated the
file_sync refactor, so the fix is re-applied to the current code path.
* docs(infographic): daytona quote-sync fix