Add Redirect Feature or Error Documentation Links

[AristurtleDev]

Summary

This PR implements a redirect system for MonoGame error documentation links. The system allows us to create stable, short URLs that can be updated without breaking external references, similar to URL shorteners.

How it works:

• Create a redirect page in the /errors/ directory such as /errors/setupwine/index.md
• The page generates a clean URL: https://docs.monogame.net/errors/setupwine
• When accessed, it automatically redirects to the target documentation.
• If the target changes only the redirect value needs to be updated.

Example Usage

---
redirect: ./path/to/target/index.md
---

[redirect](./path/to/target.md]

Note

Due to DocFX's document processing limitations, the redirect URL must appear both in the front matter and as a link in the document body. By including it in the body, this ensures that link validation occurs, while maintaining the redirect functionality.

Notes

DocFX Processing Constraints: DocFX cannot validate YAML frontmatter values using its standard link validation. To work around this, we include the redirect URL twice:

1. In the redirect frontmatter for the redirect functionality.
2. As a markdown link in the document body for DocFX validation.

Changes Made

• docfx.json: Added /errors/**/*.md to content build process
• master.tmpl: Change from redirect_url to redirect property
  • Reason: redirect_url is a DocFX reserved property that bypasses normal processing and skips conceptual.extensions.js, which we need for proper .md to .html link transformations
• conceptual.extensions.js: Added transformation logic for model.redirect
  • Converts .md extensions to .html in the redirect URLs
  • enables use of standard DocFX relative links in both frontmatter and document body
  • Maintains link validation compatibility

[dellis1972]

@AristurtleDev

Can we use the errors folder for actual error pages as well (not just redirections? )

e.g I would like to have docs.monogame.net/error/mgfx0001 which is an actual coded error message we have in the code. The page mgfx0001.md would have info on the error, what it is and how to work around it and links to other docs.

[SimonDarksideJ]

Yes @dellis1972 , that folder is a docs area just like any other I believe. So any document with frontmatter should work.

We can simply try it out if you wish