layout-valign="bottom" with Typst subfigures

Bug description

Using the latest nightly of quarto, subfigure cations are now working (thanks @cscheid!). But when I use layout-valign="bottom" the figures are not bottom-aligning (see example below).

The typst grid uses align: auto, and your code does not add any align attributes. One problem is that if you set align: bottom on grid, then captions will align to the bottom, so it may be that you need to specify grid.cell and then specify the alignment only for figure-containing cells?

Steps to reproduce

Sample code from a working document:

::: {#fig-locking layout-ncol="2" layout-valign="bottom"}

![The locking holes on the implant plate](img/simia_locking_hole.png){#fig-simiaLockingHole}

![Locking hole unit](img/simia_locking_unit.png){#fig-simiaLockingUnit}

In our optimized design, we introduced a locking mechanism.

:::

Expected behavior

Typst output follows layout-valign

Actual behavior

layout-valign is not currently implemented AFAICT.

Your environment

Quarto 1.5.39

Quarto check output

▶︎ quarto check
Quarto 1.5.39
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.2.0: OK
      Dart Sass version 1.70.0: OK
      Deno version 1.41.0: OK
      Typst version 0.11.0: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.5.39
      Path: /Applications/quarto/bin

[✓] Checking tools....................OK
      TinyTeX: v2024.05
      Chromium: (not installed)

[✓] Checking LaTeX....................OK
      Using: TinyTex
      Path: /Users/ian/Library/TinyTeX/bin/universal-darwin
      Version: 2024

[✓] Checking basic markdown render....OK

[✓] Checking Python 3 installation....OK
      Version: 3.12.1
      Path: /Users/ian/.pyenv/versions/3.12.1/bin/python3
      Jupyter: (None)

      Jupyter is not available in this Python installation.
      Install with python3 -m pip install jupyter

[✓] Checking R installation...........OK
      Version: 4.4.0
      Path: /Library/Frameworks/R.framework/Resources
      LibPaths:
        - /Library/Frameworks/R.framework/Versions/4.4-arm64/Resources/library
      knitr: (None)
      rmarkdown: (None)

      The knitr package is not available in this R installation.
      Install with install.packages("knitr")
      The rmarkdown package is not available in this R installation.
      Install with install.packages("rmarkdown")

Start by rendering the provided Quarto example to Typst and compare its output with the expected bottom alignment. Then trace how layout-valign is handled for Typst grids and captions; done means figure-containing cells follow bottom alignment while captions remain correctly placed.