

In every `results` reference, `:run_dir` must be named/represented:
$acme.results.:last()                  # last of everything that has no template (implies `*:last()`)
$acme.results.*:last()                 # last of everything that has no template
$acme.results.one/2026-01-01_01-01-01  # run that has 1-level template `one/:run_dir` with a specific name


$acme.files.:all():last()            # last where there was no template, grouped by `:filename`
From these:
-named_files/acme/one.csv/a1a2a3....csv
-named_files/acme/one.csv/b1b2b3....csv
-named_files/acme/two.csv/c1c2c3....csv
-named_files/acme/two.csv/d1d2d3....csv
Yields these:
-named_files/acme/one.csv/b1b2b3....csv
-named_files/acme/two.csv/d1d2d3....csv


$acme.results.one/*:last()             # last of everything that has 1-level template `one/:run_dir`
$acme.results.one/:all():last()        # last of everything that has 1-level template `one/:run_dir`

