Add `eq.dot` for ≐

[NamorNiradnug]

There are eq.dots and eq.quest, would be nice to have eq.dot for \u{2250} (≐).

[isuffix]

Note that this was attempted by #87 which was closed due to uncertainty about how to name the difference between the up/down variants: ≐/⩦

So this issue should probably also serve as a place to discuss the down variant and any other dotted symbol variants.

[MDLC01]

I'll refer you to Section 9.1 of the Symbol List for sym document for more context. This is definitely a symbol we want to name at some point, but I wouldn't say it is a priority as there are easier-to-name symbols that can be dealt with first. Symbols with decorations in general are very hard to name because there can exist many subtly different variants. We are adding a few more decorated symbols in #157 because they are fairly straight forward to name.

[dccsillag]

I slightly disagree with this not being a priority -- if I recall, this is a very common symbol for people in engineering. In fact, I'm quite surprised it wasn't already available.

I'll try to look into the existing discussions within the next few days. But personally I would consider adding eq.dot just to have this specific symbol, and later have the more complete design featuring also the other variants.

[MDLC01]

You are right, I should have said it is not a priority for me. But of course if you want to look into it that would be great.

And since ultimately we will probably want eq.dot to resolve to ≐, adding it now without adding any other variant for now is totally an option.

[NamorNiradnug]

I think eq.dot should resolve to ≐ for consistency with plus.dot, minus.dot and tilde.dot.

I also would propose eq.dot.t for ≐ and eq.dot.b for ⩦.