I'm thinking what I am describing would be something along the lines of "Lead Developer", I've also hear the term "Principle Developer".
Either of these is fine, don't overthink it.
Your job title in a position like this means very little in the long (or even short) term. Your responsibilities and professional reputation are what's important.
I would agree for the most part with Player One but with one slight change: the Leadership roles do stand out.
My company uses "Lead Developer" and "Lead Engineer", where developer is typically programming specific and engineer includes programming as well as infrastructure work.
But like Player One says, don't over-think this. Either title will be fine. ...
Title shouldn't mean as much internal to your team, but they typically do convey something to other internal teams and external companies.
You mentioned enjoying:
Creating Code Standard Documents for the other devs to follow
Planning Product Development and Timelines (planning meeting etc)
Mentoring other developers