Error rewrites (#43)

* pcap: reuse Frame memory

* slog: reduce heap allocations of addresses; also prevent heap alloc of dhcp options in pcap

* dns: heapless improvement; add StackAsync buffer for more heapless operation; start thinking of errors

* errors: begin standardise errors in lneto

* errors: finish standardization of errors

* fix merge issues

* add more lneto errors to rest of package

* format errors.go

dhcpv4/server.go

@@ -10,6 +10,8 @@ import (
 	"github.com/soypat/lneto/internal"
 )
 
+var errOptionNotFit = errors.New("DHCPv4: options dont fit")
+
 type Server struct {
 	connID       uint64
 	nextAddr     netip.Addr