feat(arch): the FP8-to-halfword conversion pairs

Assisted-by: GLM 5.3 Flash

asm/extension_test.go

@@ -321,6 +321,10 @@ func TestExtensionNamesARM64(t *testing.T) {
 		"ZBF1CVTLT",
 		"ZBF2CVT",
 		"ZBF2CVTLT",
+		"ZF1CVT",
+		"ZF1CVTLT",
+		"ZF2CVT",
+		"ZF2CVTLT",
 		"ZBFADD",
 		"ZBFCLAMP",
 		"ZBFMAX",
@@ -493,7 +497,7 @@ func TestExtensionNamesARM64(t *testing.T) {
 	if strings.Join(got, ",") != strings.Join(want, ",") {
 		t.Errorf("ExtensionNames(ARM64) = %v, want %v", got, want)
 	}
-	if n := len(arch.Extensions(arch.ARM64)); n != 503 {
-		t.Errorf("the family registers %d instructions, want 503", n)
+	if n := len(arch.Extensions(arch.ARM64)); n != 507 {
+		t.Errorf("the family registers %d instructions, want 507", n)
 	}
 }