Review wording of tooltips in forms tables

[stephenmk]

Discussed in #113

^{Originally posted by parfait8566 October 17, 2024}
This is just a nitpick and not related to the new symbol changes, but shouldn't the table distinguish between rare forms and readings (or both)?
In the table for 氷室, if you hover on ひょうしつ it says "rarely used form" when "rarely used reading" would be more correct.
I guess it could get annoying to check if there are both [rK] and [rk] tags to display something like "rarely used form and reading" though.