feat: add Bailian image generation support

lib/server/image-template-input.ts

@@ -89,7 +89,7 @@ function optionalScale(value: unknown): number | undefined {
 
 function normalizeImageEngine(value: unknown): ImageTemplate["settings"]["engine"] | undefined {
   const text = optionalText(value, 20);
-  if (text === "jimeng" || text === "evolink") return text;
+  if (text === "jimeng" || text === "evolink" || text === "bailian") return text;
   return undefined;
 }