!expr invalide with message in chunk option

Bug description

!expr in chunk option don't work for message while it works e.g. error.

Steps to reproduce

---
title: test knitr
# validate-yaml: false
---

```{r}
#| label: chunk1

show.message <- FALSE
```

```{r}
#| label: chunk2
#| error: !expr "show.message"

message("this works")
```

```{r}
#| label: chunk3
#| message: !expr "show.message"

message("this doesn't work")
```

Expected behavior

This should not produce an error message.
Note that with validate-yaml: false not commented I'm able to render the quarto file

Actual behavior

Produce the following error message:

ERROR: Validation of YAML cell metadata failed.
In file test.qmd
(line 21, columns 13--33) Field "message" has value !expr "show.message", which must instead be one of: `true`, `false`, `NA`

Your environment

Ubuntu 24.04
Quarto 16.04
VSCodium 1.92.2

Quarto check output

quarto check
Quarto 1.6.40
[✓] Checking environment information...
      Quarto cache location: /home/lbeaulaton/.cache/quarto
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.4.0: OK
      Dart Sass version 1.70.0: OK
      Deno version 1.46.3: OK
      Typst version 0.11.0: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.6.40
      Path: /opt/quarto/bin

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

[✓] Checking LaTeX....................OK
      Using: Installation From Path
      Path: /usr/bin
      Version: 2023

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

[✓] Checking Python 3 installation....OK
      Version: 3.12.3
      Path: /usr/bin/python3
      Jupyter: 5.3.2
      Kernels: python3

(\) Checking Jupyter engine render....Traceback (most recent call last):
  File "/opt/quarto/share/jupyter/jupyter.py", line 21, in <module>
    from notebook import notebook_execute, RestartKernel
  File "/opt/quarto/share/jupyter/notebook.py", line 20, in <module>
    from nbclient import NotebookClient
ModuleNotFoundError: No module named 'nbclient'
[✓] Checking Jupyter engine render....OK