Fix broken link

[adit-0132]

Description

• Added anchors of the form {#sec-...} to all chapter headings
• Updated links in the introduction and elsewhere to point to the new anchors
• Standardised link text to match the corresponding chapter titles
• Ran Lychee on the built guide to confirm, and also manually checked the guide for broken links

This ensures consistent internal navigation, enables cross-references,
and improves maintainability of the R Dev Guide.

[hturner]

Thanks for picking up this issue. What we actually want to do here is link to different chapters of the guide, so the link should go to https://contributor.r-project.org/rdevguide/chapters/message_translations.html. However, to do this properly, we need to add anchors to all the chapters.

For example, the header in the Message Translations chapter (L7) could be updated to

# Message Translations {#sec-message-translations}

and then when we want to reference it, e.g. in the introduction, we use this new anchor, e.g.

2. Contributing to translations: Refer to [Translations](#sec-message-translations).

Using the sec prefix will also allow us to use cross-references, which might be useful, though I think it is more helpful to link the chapter title rather than the chapter number, even though the link text can then get out of sync.

So this is a bigger issue than it first appears and it would be great if you could work on this as follows:

• Add anchors to all chapter headings of the form {#sec-message-translations}
• Check and update any links to chapters, updating both the link text (which should match the chapter title) and the link (to your new anchor). This will be somewhat manual, I would review the whole of the introduction and use search tools to find old links elsewhere (e.g. #ReviewBugs). Be careful to check the context - is the target a different chapter, or a section of the same chapter? You should create a fork of the rdevguide repo and check it out locally.
• For a through check, install Lychee (from the Assets of the latest release), build the dev guide locally (running quarto render from the terminal at the root of the repo) and then run the built HTML through Lychee to check for broken links:

lychee --verbose '_book/**/*.html'

Hopefully you'll be able to work out how to fix any broken links discovered by Lychee, but you can ask here if you're unsure about anything.

We could add Lychee to GitHub actions to check for broken links, but we still need to fix them, so I think it's worth fixing everything first, then adding Lychee to GitHub actions to catch broken links in later changes to the guide.

[adit-0132]

Thanks for the detailed explanation. I'd love to work out this whole issue and get started now.