doc/dev/notes/vanguards.md contradicts vanguards spec

According to the vanguards spec, there's a slight asymmetry between lite and full vanguard client rend circuits:

• lite: C -> G -> L2 -> Rend
• full: C -> G -> L2 -> L3 -> Rend

But according to vanguards.md, a client rendezvous circuit is a STUB circuit, in other words:

• lite: C -> G -> L2 -> Rend (like in the vanguards spec)
• full: C -> G -> L2 -> L3 (== Rend) (wrong)

So in other words, clients using full vanguards always use one of their L3 vanguards as the rendezvous point. This seems bad, because it means clients leak their L3 vanguards to the services they are connecting to (this could be a DoS vector: if you find out someone's vanguards, you can DoS them by DoSing the vanguards, at least until the vanguards are rotated).