Previously in a member expression like `foo.x` or `foo[3]`, `foo` had to be an identifier. You could not do something like `f().x` (and if you tried, you got a cryptic error). Rather than make the error better, we should just accept any expression to be the LHS of a member expression (aka its 'object').
This does knock our "parse lots of function calls" from 58 to 55 calls before it stack overflows. But I think it's fine, we'll address this in https://github.com/KittyCAD/modeling-app/pull/6226 when I get back to it.
Closes https://github.com/KittyCAD/modeling-app/issues/7273
