quarto preview: disabling navigate has no effect

Bug description

When I have a file open in the browser within quarto preview, then updating an unrelated file redirects the browser to the updated file. This is despite setting project.preview.navigate: false in _quarto.yml. According to the docs that should disable this behavior.

Steps to reproduce

• Serve project below using quarto preview .
• Open the browser to a.html
• Make an edit to b.qmd on the filesystem

_quarto.yml:

project:
  type: website
  render:
    - a.qmd
    - b.qmd
  preview:
    navigate: false

a.qmd:

---
---

Test `A.qmd`

b.qmd:

---
---

Test `B.qmd`

Expected behavior

• a.html stays open in the browser.

Actual behavior

• URL bar & browser window updates to b.html.

Your environment

No response

Quarto check output

$ quarto check
Quarto 1.6.36
[✓] Checking environment information...
      Quarto cache location: /Users/bbloniarz/Library/Caches/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: 1.6.36
      Path: /Applications/quarto/bin

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

[✓] Checking LaTeX....................OK
      Tex:  (not detected)

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

[✓] Checking Python 3 installation....OK
      Version: 3.12.5
      Path: /Users/bbloniarz/.pyenv/versions/3.12.5/bin/python3
      Jupyter: (None)

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

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

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

Reproduce with quarto preview . using _quarto.yml, a.qmd, and b.qmd, then trace the preview handling for project.preview.navigate. Verify the setting is read and applied when b.qmd changes; done means a.html remains open instead of navigating to b.html.