feat: added APF for CW in Icom

internal/cat/cat.go

@@ -415,6 +415,7 @@ type IcomTXState struct {
 	NR        bool   `json:"nr"`
 	NRLevel   int    `json:"nr_level"`
 	ANF       bool   `json:"anf"`
+	APF       bool   `json:"apf"` // audio peak filter (CW only)
 	AGC       string `json:"agc,omitempty"` // FAST | MID | SLOW
 	Preamp    int    `json:"preamp"`        // 0=off, 1=P.AMP1, 2=P.AMP2
 	Att       int    `json:"att"`           // dB attenuation, 0=off
@@ -450,6 +451,7 @@ type IcomController interface {
 	SetNR(bool) error
 	SetNRLevel(int) error
 	SetANF(bool) error
+	SetAPF(bool) error
 	SetAGC(string) error
 	SetPreamp(int) error
 	SetAtt(int) error