vson8 throws a raw parse error while son8/wson8 render from a bare name

[zkasuran]

vson is listed by getFootprintNames(), but calling it from a bare name crashes:

fp.string("vson8").circuitJson() // throws a raw ZodError (Required: p, w, grid, pinw, pinh)
fp.string("son8").circuitJson()  // 8 pads
fp.string("wson8").circuitJson() // 9 pads

Both sibling SON-family footprints (son, wson) default their dimensions and render from a bare name. vson alone declares p/w/grid/pinw/pinh with no defaults (the def carries a comment "can't use defaults because there is not a lot of common dimensions"), so any bare vsonN throws. A user who picks vson8 from the footprint list gets a raw parse error instead of a footprint.

I have a fix and will open a PR that references this issue.