Add a default picture-printing dialog and right-click Print action

[jonnyace]

Printing a picture should be easier to discover and configure in Omarchy.

On my installation, imv’s default Ctrl+P binding sends the current image directly to lp, without a dialog to choose the printer or page settings.

Could Omarchy include:

• A Print… action when right-clicking a picture in Files.
• A print dialog with printer, copies, paper size, and orientation options, fitting the image to the page.
• Access to the same dialog from the image viewer, appearing in front and keeping the viewer responsive.

Super+P could also be considered as a printing shortcut, though it currently toggles pseudo tiling.

[jonnyace]

Implementation PR: #10418