Stabilize modal rendering and sequential Gemini flow

backend/handlers/api.go

@@ -337,14 +337,25 @@ func (a *App) searchMedia(c *gin.Context) {
 	}
 	if geminiErr != nil && len(recommended) == 0 {
 		warning := geminiErr.Error()
-		fallback := services.BuildFallbackRecommendations(scored, 20, "")
-		a.debug("search fallback summary", summarizeRecommendationResults(fallback, time.Since(started), warning))
-		a.Hub.Broadcast("progress", gin.H{"type": "search", "status": "Gemini Vision fallback to ranked results", "progress": 90, "message": warning})
-		c.JSON(http.StatusOK, gin.H{"results": fallback, "warning": warning, "queries": queryVariants})
+		if strings.Contains(warning, "gemini api key is not configured") {
+			fallback := services.BuildFallbackRecommendations(scored, 20, "")
+			a.debug("search fallback summary", summarizeRecommendationResults(fallback, time.Since(started), warning))
+			c.JSON(http.StatusOK, gin.H{"results": fallback, "warning": warning, "queries": queryVariants})
+			return
+		}
+		a.debug("search fallback summary", summarizeRecommendationResults([]services.AIRecommendation{}, time.Since(started), warning))
+		a.Hub.Broadcast("progress", gin.H{"type": "search", "status": "Gemini Vision returned no usable results", "progress": 90, "message": warning})
+		c.JSON(http.StatusOK, gin.H{"results": []services.AIRecommendation{}, "warning": warning, "queries": queryVariants})
 		return
 	}
 
 	merged := services.MergeRecommendations(recommended, scored, 20)
+	if len(merged) == 0 && len(recommended) > 0 {
+		warning := "Gemini가 대부분의 후보를 부정적으로 평가해 표시할 결과가 없습니다."
+		a.debug("search fallback summary", summarizeRecommendationResults([]services.AIRecommendation{}, time.Since(started), warning))
+		c.JSON(http.StatusOK, gin.H{"results": []services.AIRecommendation{}, "warning": warning, "queries": queryVariants})
+		return
+	}
 	merged = services.RandomizeTopRecommendations(merged, 8)
 	warning := ""
 	if geminiErr != nil {