Add option to index and search for special characters

[bglw]

Discussed in #773

^{Originally posted by argl January 17, 2025}
When evaluating pagefind for indexing/searching MDN content (nice demo!), I noticed there are a lot of pages on MDN with the literal HTML tag as the title, for example the <table> documentation page.

Ideally, I would search for <table> and get to the main HTML table documentation page, but unfortunately, this is not the case. I understand that this is a wacky request very specific to the MDN content, but I am wondering if this can be done, and how? I do have full control over the HTML that is passed to the indexer.

Thanks for this great library!