Wellp, I just got some “fairy lights”, and while the rgb ones can be tricky unless you want to set specific colors, the plain WW ones are 3-wire but can be “turned into” 2-wire by just joining the 2 channels.
From there, yeah, a small length tie-wrapped to a rope, powered with coin-cell + resistor for just a faint glow should be enough and cheap-enough to do on a budget.
Vipon has/had a 16-pack of shorter-length FLs that come with a small holder for coin-cell and with a built-in switch. Those made to stick the lights into bottles have an elongated frustrum for a holder and take stacked button-cells
but the other ones have the flat coin-cell holders. Hang on…
https://www.amazon.com/dp/B0834W68MC
and if anyone’s interested
https://www.vipon.com/product/7246422-Fog-Rain-Pack-LED-Fairy-20LED-amazon-coupons
for 9bux’n’change for the set of 16.
Go crazy…
(Bah, c&p the link instead of just clicking on it.)