feat: screenshot and print utils

[mscolnick]

• Add 4 new browser utilities: PrintPageButton, print_page(), ScreenshotButton, and screenshot() — each as a button widget + programmatic function pair
• Screenshot utilities dynamically load modern-screenshot from esm.sh for zero Python dependencies

New Widgets

Print

PrintPageButton — a button that opens the browser print dialog:

from moutils import PrintPageButton

btn = PrintPageButton()
btn

print_page() — programmatically trigger print (e.g. behind a run_button):

from moutils import print_page

print_page_button = mo.ui.run_button(label="Print page")
print_page_button

# in another cell:
if print_page_button.value:
    print_page()

Screenshot

ScreenshotButton — a button that captures a DOM element as a PNG download:

from moutils import ScreenshotButton

btn = ScreenshotButton(locator="body", filename="page.png")
btn

screenshot() — programmatically capture a screenshot (e.g. of a specific cell):

from moutils import screenshot

take_screenshot = mo.ui.run_button(label="Take screenshot")
take_screenshot

# in another cell:
if take_screenshot.value:
    screenshot(locator="[data-cell-name='my_cell']", filename="page.png")