Backfill partial Gemini results and restore modal iframe

TODO.md

@@ -460,6 +460,21 @@
 - There is one known local commit that has not been pushed because the remote repo reported an unpacker error.
 
 ## Recent Change Log
+- Date: `2026-03-16`
+- What changed:
+  - When Gemini batch evaluation is only partially successful, the API now explicitly backfills the final list with preview-capable ranked candidates instead of leaving the visible result set too thin.
+  - Result modal behavior was switched so Envato and Artgrid open their actual item webpages inside the modal iframe again, while Google Video still uses the YouTube embed path.
+  - Frontend asset version was bumped again to force clients off stale preview-handling code.
+- Why it changed:
+  - The new debug log showed `recommendedCount: 2` plus one failed Gemini batch, but the final visible list still collapsed to `6` items even though the raw pool was `25`.
+  - The user wants in-modal login/download for Envato and Artgrid rather than preview-only media mode.
+- How it was verified:
+  - log review from `ai-media-hub-2026-03-16T06-00-31-359Z.log`
+  - code inspection of post-Gemini backfill and modal rendering path
+- What is still risky or incomplete:
+  - Artgrid candidate volume is still often low because SearXNG is returning many `0`-result queries for current Artgrid query templates.
+  - If a browser still holds older frontend assets, a hard refresh may be required before the latest modal/preview behavior appears.
+
 - Date: `2026-03-16`
 - What changed:
   - Significantly increased backend debug logging volume and routed it into the existing WebSocket `debug` stream so the in-app `Logs` panel captures much deeper request, search, preview, Gemini, and ranking traces.

backend/handlers/api.go

@@ -458,6 +458,14 @@ func (a *App) searchMedia(c *gin.Context) {
 	}
 
 	merged := services.MergeRecommendations(recommended, scored, 20)
+	if geminiErr != nil {
+		merged = services.BackfillRecommendations(
+			merged,
+			scored,
+			12,
+			"Gemini 배치 일부가 실패해 미리보기 가능한 상위 후보를 보강했습니다.",
+		)
+	}
 	merged = services.RandomizeTopRecommendations(merged, 8)
 	warning := ""
 	if geminiErr != nil {

backend/services/ranker.go

@@ -355,6 +355,38 @@ func MergeRecommendations(recommended []AIRecommendation, ranked []SearchResult,
 	return merged
 }
 
+func BackfillRecommendations(existing []AIRecommendation, ranked []SearchResult, limit int, reason string) []AIRecommendation {
+	merged := make([]AIRecommendation, 0, min(limit, len(ranked)))
+	seen := map[string]bool{}
+	for _, item := range existing {
+		if item.Link == "" || seen[item.Link] {
+			continue
+		}
+		seen[item.Link] = true
+		merged = append(merged, item)
+	}
+	for _, item := range ranked {
+		if len(merged) >= limit || item.Link == "" || seen[item.Link] {
+			continue
+		}
+		if strings.TrimSpace(item.ThumbnailURL) == "" && strings.TrimSpace(item.PreviewVideoURL) == "" {
+			continue
+		}
+		seen[item.Link] = true
+		merged = append(merged, AIRecommendation{
+			Title:           item.Title,
+			Link:            item.Link,
+			Snippet:         item.Snippet,
+			ThumbnailURL:    item.ThumbnailURL,
+			PreviewVideoURL: item.PreviewVideoURL,
+			Source:          item.Source,
+			Reason:          reason,
+			Recommended:     false,
+		})
+	}
+	return merged
+}
+
 func max(a, b int) int {
 	if a > b {
 		return a

frontend/app.js

@@ -513,10 +513,8 @@ function openResultModal(item) {
   resetResultModalMedia();
   if (item.source === "Google Video") {
     showResultModalFrame(buildResultModalEmbedURL(item));
-  } else if (item.previewVideoUrl) {
-    showResultModalVideo(item.previewVideoUrl);
   } else {
-    showResultModalThumbnail(item.thumbnailUrl, item.title || "");
+    showResultModalFrame(item.link || "about:blank");
   }
   showModal(resultModal);
   logEvent("result:modal:open", { title: item.title, source: item.source, link: item.link });

frontend/index.html

@@ -202,6 +202,6 @@
       </button>
     </template>
 
-    <script src="/app.js?v=20260316e" defer></script>
+    <script src="/app.js?v=20260316f" defer></script>
   </body>
 </html>