WebSocket config: Add heartbeatPeriod for client & server (#4065)

https://github.com/XTLS/Xray-core/pull/4065#issuecomment-2502627154

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Co-authored-by: RPRX <63339210+RPRX@users.noreply.github.com>

infra/conf/transport_internet.go

@@ -149,6 +149,7 @@ type WebSocketConfig struct {
 	Path                string            `json:"path"`
 	Headers             map[string]string `json:"headers"`
 	AcceptProxyProtocol bool              `json:"acceptProxyProtocol"`
+	HeartbeatPeriod     uint32            `json:"heartbeatPeriod"`
 }
 
 // Build implements Buildable.
@@ -178,6 +179,7 @@ func (c *WebSocketConfig) Build() (proto.Message, error) {
 		Header:              c.Headers,
 		AcceptProxyProtocol: c.AcceptProxyProtocol,
 		Ed:                  ed,
+		HeartbeatPeriod:     c.HeartbeatPeriod,
 	}
 	return config, nil
 }