v0.8.6

• small_multiple() now lets users customise the order of models (along the
  x-axis) and submodels (mapped to colour) via the model_order and
  submodel_order arguments, matching the behaviour of dwplot() (Issue #108).
  Added tests covering this behaviour.
• Fixed the documented defaults for small_multiple()'s dodge_size (.4) and
  by_2sd (FALSE) arguments, and removed dead point-positioning code.
• Replaced the now-unmaintained ggstance dependency with native ggplot2
  horizontal geoms (geom_linerange(orientation = "y") + position_dodge()).
  This removes the size-aesthetic deprecation warning in dwplot()
  (Issue #120) without changing any plot output.
• Replaced the deprecated aes_string() (in add_brackets()) and is.ggplot()
  (in relabel_predictors()) calls to be compatible with ggplot2 4.0.
• Internal cleanup: de-duplicated dw_tidy() and the layer-building code in
  dwplot(), removed a fragile join and dead code in add_brackets(), and
  dropped unused/no-op code. No user-facing behavior changes.