Constant OWN_INSTANCE_ANCESTOR_HOPS 

pub(crate) const OWN_INSTANCE_ANCESTOR_HOPS: usize = 8;

Max ancestor hops to walk from this MCP process before giving up — bounds the fallback search (see own_instance_pids’s doc comment for why this is a fallback, not the primary signal), while never walking so far up the tree (e.g. to explorer.exe) that “same instance” degrades into “everything on the desktop.”