feat: replicate channel flux model

relay/channel/replicate/constants.go

@@ -0,0 +1,12 @@
+package replicate
+
+const (
+	// ChannelName identifies the replicate channel.
+	ChannelName = "replicate"
+	// ModelFlux11Pro is the default image generation model supported by this channel.
+	ModelFlux11Pro = "black-forest-labs/flux-1.1-pro"
+)
+
+var ModelList = []string{
+	ModelFlux11Pro,
+}