fix(hysteria2): restore missing masquerade config in inbound form (#4316)

* fix(hysteria2): restore missing masquerade config in inbound form

Fixes #4303

The Hysteria2 Masquerade option was missing from the Stream settings
tab after the v3.0.0 form rewrite. Added the UI form and ensured the
masquerade block is passed through in subscription JSON generation.

sub/subJsonService.go

@@ -447,6 +447,9 @@ func (s *SubJsonService) genHy(inbound *model.Inbound, newStream map[string]any,
 	if udpIdleTimeout, ok := hyStream["udpIdleTimeout"].(float64); ok {
 		outHyStream["udpIdleTimeout"] = int(udpIdleTimeout)
 	}
+	if masquerade, ok := hyStream["masquerade"].(map[string]any); ok {
+		outHyStream["masquerade"] = masquerade
+	}
 	newStream["hysteriaSettings"] = outHyStream
 
 	if finalmask, ok := hyStream["finalmask"].(map[string]any); ok {