Love the idea. I think widgets is a good term. I wonder if nostr:npub1p4kg8zxukpym3h20erfa3samj00rm2gt4q5wfuyu3tg0x3jg3gesvncxf8 's hypernotes that he demoed in Madeira would be interesting to consider.
Just spent a little time trying to find a more suitable/constrained language for this but can't find anything better than HTML (and probably JS). The majority of runtimes support web, maybe not ideal but best we've got I think