fig-align not working for indented code chunks

I have:

• searched the issue tracker for similar issues
• installed the latest version of Quarto CLI
• formatted my issue following the Bug Reports guide

Bug description

fig-align: center is not working for indented code chunk

Steps to reproduce

---
title: abc
format: revealjs
---

# Test

-   abc

    ```{mermaid}
    %%| fig-align: center
    graph LR
        abc --> cde
    ```

Actual behavior

Resulting figure not indented

Expected behavior

resulting figure indented

Your environment

• VSCode: 1.105.1
• debian trixie (devcontainer on remote rocky 9 machine)
• MacOS 15.7.1 (24G231)

Quarto check output

Quarto 1.7.33
[✓] Checking environment information...
      Quarto cache location: /home/stefan/.cache/quarto
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.6.3: OK
      NOTE: Dart Sass version 1.59.1 does not strictly match 1.85.1 and strict checking is enabled. Please use 1.85.1.
      Deno version 1.46.3: OK
      Typst version 0.13.0: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.7.33
      Path: /opt/conda/envs/dev/bin

[✓] Checking tools....................OK
      TinyTeX: v2025.09
      Chromium: (not installed)

[✓] Checking LaTeX....................OK
      Using: TinyTex
      Path: /home/stefan/.TinyTeX/bin/x86_64-linux
      Version: 2025

[✓] Checking Chrome Headless....................OK
      Chrome:  (not detected)

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

[✓] Checking Python 3 installation....OK
      Version: 3.13.7 (Conda)
      Path: /opt/conda/envs/dev/bin/python
      Jupyter: 5.8.1
      Kernels: python3

[✓] Checking Jupyter engine render....OK

[✓] Checking R installation...........(None)

      Unable to locate an installed version of R.
      Install R from https://cloud.r-project.org/

Start by rendering the provided QMD example with Quarto 1.7.33 and the revealjs format, checking how the Mermaid figure behaves inside the indented list item. Trace the figure-alignment handling for indented code chunks and compare it with a non-indented chunk. Done means the resulting figure stays centered and correctly indented within the list item.