Align console behavior with operator routing and image workflow expectations

Constraint: Must preserve current exchange-rate logic, same-group routing boundary, and temporary image-file behavior while fixing UX-visible inconsistencies.
Rejected: Large frontend chunk refactor | introduced risky circular chunking and did not improve deliverability for this rollout.
Confidence: medium
Scope-risk: moderate
Directive: Keep channel failover constrained to the selected group and preserve Beijing-day semantics for user cache dashboard metrics.
Tested: go test ./controller ./model ./service ./common -count=1; npm run build; remote smoke on source deployment at http://38.76.218.56:18081/ plus /api/status and /api/image-studio/settings.
Not-tested: Browser-driven end-to-end verification of every console page interaction.

router/api-router.go

@@ -263,6 +263,7 @@ func SetApiRouter(router *gin.Engine) {
 		imageStudioRoute := apiRouter.Group("/image-studio")
 		imageStudioRoute.Use(middleware.UserAuth())
 		{
+			imageStudioRoute.GET("/settings", controller.GetImageStudioSettings)
 			imageStudioRoute.POST("/generate", controller.SubmitImageStudioGenerate)
 			imageStudioRoute.POST("/edit", controller.SubmitImageStudioEdit)
 			imageStudioRoute.GET("/task/:id", controller.GetImageStudioTask)