[feat] Include class name for ruby method calls

[dalehamel]

Currently without the class name, many ruby stacks aren't especially useful:

For example, the above chain of "call" repeated is a common pattern for middlewares. They all implement a "call" method, but we don't get to see what the actual middleware name is.

I filed a similar issue for rbspy some time ago:

rbspy/rbspy#379

I think that it may be possible to update the ruby bpf unwinder, but it would be a fairly major overhaul. We currently only push the iseq body to userspace, but i think we'd need to push instead the rb_callable_method_entry_t.

I think that should let us get a handle to both the class and the actual method definition, though it will require some indirection. This is how ruby's own unwinder seems to work:

https://github.com/ruby/ruby/blob/f2a7e48deadb9101d49c9b613abf5a83c9e1dd49/vm_backtrace.c#L1997-L2002

We should still be able to get the line numbers and filename, as it seems the iseq is also accessible from rb_method_definition_struct, via the "iseq" entry.

[dalehamel]

FYI i have a working prototype of this that I accidentally pushed in #735 but it isn't ready for upstreaming (mistakenly opened against this repo instead of my fork, to stage a "draft pull request"), it is based on the work I did in rbspy/rbspy#397 to achieve the same thing, and only works in ruby 3.3.0+ as it depends on ruby/ruby@abff5f6 first released in 3.3.0 for easier access to the classpath (prior to this, it had to be looked up from an ivar)

I'll try and get this tidied up to be upstreamed, but it depends on #710 for the support for unwinding 3.3.0 so can't be upstreamed until that is sorted out.