[FR] Add support to reference custom field handles in element queries’ select params

[rungta]

#16318 and #16729 gave us the ability to reference custom field handles in WHERE and ORDER BY SQL expressions. Would be handy to have the same feature available for SELECT params as well, to enable queries such as this:

{% set years = craft.entries
  .section('events')
  .addSelect('YEAR([[eventDate]])')
  .column()
  |unique %}