types: add order-independent endpoint comparison

Add EndpointsChanged function that compares endpoint slices
without regard to ordering. Uses netip.AddrPort.Compare with
slices.SortFunc to enable accurate change detection.

Update PeerChangeFromMapRequest to only include endpoints in
PeerChange when they actually changed, avoiding unnecessary
updates to peers.

hscontrol/types/node.go

@@ -509,8 +509,10 @@ func (node *Node) PeerChangeFromMapRequest(req tailcfg.MapRequest) tailcfg.PeerC
 		}
 	}
 
-	// TODO(kradalby): Find a good way to compare updates
+	// Compare endpoints using order-independent comparison
+	if EndpointsChanged(node.Endpoints, req.Endpoints) {
 		ret.Endpoints = req.Endpoints
+	}
 
 	now := time.Now()
 	ret.LastSeen = &now
@@ -518,6 +520,32 @@ func (node *Node) PeerChangeFromMapRequest(req tailcfg.MapRequest) tailcfg.PeerC
 	return ret
 }
 
+// EndpointsChanged compares two endpoint slices and returns true if they differ.
+// The comparison is order-independent - endpoints are sorted before comparison.
+func EndpointsChanged(oldEndpoints, newEndpoints []netip.AddrPort) bool {
+	if len(oldEndpoints) != len(newEndpoints) {
+		return true
+	}
+
+	if len(oldEndpoints) == 0 {
+		return false
+	}
+
+	// Make copies to avoid modifying the original slices
+	oldCopy := slices.Clone(oldEndpoints)
+	newCopy := slices.Clone(newEndpoints)
+
+	// Sort both slices to enable order-independent comparison
+	slices.SortFunc(oldCopy, func(a, b netip.AddrPort) int {
+		return a.Compare(b)
+	})
+	slices.SortFunc(newCopy, func(a, b netip.AddrPort) int {
+		return a.Compare(b)
+	})
+
+	return !slices.Equal(oldCopy, newCopy)
+}
+
 func (node *Node) RegisterMethodToV1Enum() v1.RegisterMethod {
 	switch node.RegisterMethod {
 	case "authkey":