"Implementor" should not be a typo

[SOF3]

Introduced in the January 2025 edition #1200 (comment), "implementor" is autocorrected to "implementer". However:

• This is the term used in documentation generated by rustdoc
• "Implementor" is not significantly less common than "implementer", depending on the time

(ngram link retrieved from https://english.stackexchange.com/a/358111/198517)