Bug: derive_summary_records requires by_vars in dataset

[bundfussr]

What happened?

The checks in derive_summary_records() are too restrictive: by_vars are expected in dataset although the code doesn't require it.

Session Information

No response

Reproducible Example

library(dplyr)
adbs <- tribble(
  ~AVISITN, ~ADY,  ~AVAL,
  1,           1,  10,
  2,           8,  12,
  3,          15,  10,
  3,          17,  14
) %>%
  mutate(USUBJID = "1")

derive_summary_records(
  dataset_add = adbs,
  by_vars = exprs(USUBJID),
  set_values_to = exprs(
    AVAL = mean(AVAL),
    PARAMCD = "MEANALL"
  )
) %>%
  derive_summary_records(
    dataset_add = adbs,
    by_vars = exprs(USUBJID, AVISITN),
    set_values_to = exprs(
      AVAL = mean(AVAL),
      PARAMCD = "MEANVISIT"
    )
  )

produces

Error in `derive_summary_records()`:
! Required variable `AVISITN` is missing in `dataset`
Run `rlang::last_trace()` to see where the error occurred.

It shouldn't fail but result in

# A tibble: 4 × 4
  USUBJID  AVAL PARAMCD   AVISITN
  <chr>   <dbl> <chr>       <dbl>
1 1        11.5 MEANALL        NA
2 1        10   MEANVISIT       1
3 1        12   MEANVISIT       2
4 1        12   MEANVISIT       3