Add a resolution-phase pass (goCrossFileMethodContainsEdges) that links a Go
method to its same-named receiver type within the same package (= directory),
so a method declared in a different file from its `type` is no longer orphaned
from the struct. Runs before goImplementsEdges so cross-file methods also count
toward interface satisfaction (#584). Adds a regression test + CHANGELOG entry.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>