The PRINT command renders the current layout to a temporary PDF (reusing
the existing PDF export pipeline) and dispatches it to the OS default
printer:
- Linux/macOS: `lp` (CUPS) with `lpr` as fallback.
- Windows: ShellExecute "print" verb (compiled-in, unused on Linux).
PLOT and EXPORT still open the save-file dialog as before.
Status messages are shown in the command line during the async job.
Closes ROADMAP 1.8.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
