[Book] Cross reference doesn't work if `output-file` is used

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

Cross reference is unable to find any reference of content of a page/chapter which's output filename has been changed by the user.

Index file

---
output-file: index-es
---

# Chapter 1

This is an example.

## Section 1.1 {#sec-test}

Awesome section.

Test file

# Chapter 2

I would like to ref. @sec-test

I think that if the bug is not fixable, we can update the documentation warning the user for this constraint.
I think that this issue mainly can happen only in book projects.

Steps to reproduce

No response

Actual behavior

No response

Expected behavior

No response

Your environment

No response

Quarto check output

quarto check

[✓] Checking environment information...
      Quarto cache location: /Users/iagoba/Library/Caches/quarto
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.6.3: OK
      Dart Sass version 1.85.1: OK
      Deno version 1.46.3: OK
      Typst version 0.13.0: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.7.32
      Path: /Applications/quarto/bin

[✓] Checking tools....................OK
      TinyTeX: v2025.03.10
      Chromium: (not installed)

[✓] Checking LaTeX....................OK
      Using: TinyTex
      Path: /Users/iagoba/Library/TinyTeX/bin/universal-darwin
      Version: 2025

[✓] Checking Chrome Headless....................OK
      Using: Chrome found on system
      Path: /Applications/Google Chrome.app/Contents/MacOS/Google Chrome
      Source: MacOS known location

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

[✓] Checking Python 3 installation....OK
      Version: 3.13.2
      Path: /opt/homebrew/opt/python@3.13/bin/python3.13
      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 the issue with the provided Index file using output-file: index-es and the Test file's @sec-test reference. Start by tracing Quarto book cross-reference handling for renamed output files; done means the reference resolves correctly, or the book documentation clearly warns about this constraint.