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

x/xnet/tcppool.go

@@ -2,11 +2,11 @@ package xnet
 
 import (
 	"context"
-	"errors"
 	"log/slog"
 	"sync"
 	"time"
 
+	"github.com/soypat/lneto"
 	"github.com/soypat/lneto/tcp"
 )
 
@@ -52,7 +52,7 @@ type TCPPoolConfig struct {
 
 func NewTCPPool(cfg TCPPoolConfig) (*TCPPool, error) {
 	if cfg.EstablishedTimeout <= 0 || cfg.ClosingTimeout <= 0 {
-		return nil, errors.New("invalid timeout")
+		return nil, lneto.ErrInvalidConfig
 	}
 	n := cfg.PoolSize
 	pool := &TCPPool{