Numeric type
ts_numeric.RdNumbers are represented in Zod schema as either a number (z.number()),
or a Float64Array (z.instanceof(Float64Array)).
Examples
x <- ts_numeric(1)
x$check(1)
#> [1] 1
if (FALSE) { # \dontrun{
# this will fail
x$check(c(1, 2, 3))
x$check("a")
} # }