all: upd chlog, i18n; fix os resolv

internal/dnsforward/dnsforward.go

@@ -83,7 +83,9 @@ type DHCP interface {
 
 // SystemResolvers is an interface for accessing the OS-provided resolvers.
 type SystemResolvers interface {
-	// Addrs returns the list of system resolvers' addresses.
+	// Addrs returns the list of system resolvers' addresses.  Callers must
+	// clone the returned slice before modifying it.  Implementations of Addrs
+	// must be safe for concurrent use.
 	Addrs() (addrs []netip.AddrPort)
 }
 

internal/dnsforward/http.go

@@ -218,7 +218,7 @@ func (s *Server) defaultLocalPTRUpstreams() (ups []string, err error) {
 		return nil, err
 	}
 
-	sysResolvers := slices.DeleteFunc(s.sysResolvers.Addrs(), matcher.Has)
+	sysResolvers := slices.DeleteFunc(slices.Clone(s.sysResolvers.Addrs()), matcher.Has)
 	ups = make([]string, 0, len(sysResolvers))
 	for _, r := range sysResolvers {
 		ups = append(ups, r.String())