Reduce Gemini fallback noise and restore result volume

TODO.md

@@ -458,3 +458,17 @@
 - Artgrid source fidelity is better, but preview-video extraction is still incomplete.
 - There is now a local self-test workflow.
 - 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:
+  - Removed per-batch Gemini fallback injection so empty Gemini sub-results no longer automatically turn into many `"Gemini Vision 응답이 부족해..."` items.
+  - Relaxed final merge to keep more non-negative Gemini-reviewed candidates and allow a larger capped preview-capable filler set when the visible result list is too small.
+  - Slightly raised Envato / Artgrid caps and enrichment scope again after the stricter merge caused visible result count to collapse too far.
+  - Bumped frontend asset version to `20260316e` so clients pick up the newer preview-proxy behavior.
+- Why it changed:
+  - The user still saw too few results and too many fallback-labeled items despite the earlier filtering changes.
+- How it was verified:
+  - `go test ./...`
+- What is still risky or incomplete:
+  - If the browser is holding an older cached `app.js`, a hard refresh may still be needed before the proxied preview path is actually used on the client.

backend/services/cse.go

@@ -127,7 +127,7 @@ func (s *SearchService) SearchMedia(queries []string, enabledPlatforms map[strin
 }
 
 func (s *SearchService) EnrichResults(results []SearchResult) []SearchResult {
-	limit := minInt(len(results), 12)
+	limit := minInt(len(results), 14)
 	if limit == 0 {
 		return results
 	}

backend/services/gemini.go

@@ -255,10 +255,6 @@ User query: ` + query,
 		})
 	}
 
-	if len(recommendations) == 0 {
-		recommendations = BuildFallbackRecommendations(candidates, 8, "Gemini Vision 평가를 받지 못해 키워드 기준으로 보강된 결과입니다.")
-	}
-
 	return recommendations, nil
 }
 

backend/services/ranker.go

@@ -87,7 +87,7 @@ func RankSearchResults(query string, results []SearchResult) []SearchResult {
 }
 
 func GeminiCandidateLimit(total int) int {
-	return min(total, 12)
+	return min(total, 16)
 }
 
 func EvaluateAllCandidatesWithGemini(service *GeminiService, query string, ranked []SearchResult) ([]AIRecommendation, GeminiBatchStats, error) {
@@ -314,9 +314,9 @@ func MergeRecommendations(recommended []AIRecommendation, ranked []SearchResult,
 		merged = append(merged, item)
 	}
 
-	if len(merged) < min(6, limit) {
+	if len(merged) < min(12, limit) {
 		for _, item := range ranked {
-			if len(merged) >= min(6, limit) || item.Link == "" || seen[item.Link] {
+			if len(merged) >= min(12, limit) || item.Link == "" || seen[item.Link] {
 				continue
 			}
 			if strings.TrimSpace(item.ThumbnailURL) == "" && strings.TrimSpace(item.PreviewVideoURL) == "" {
@@ -330,7 +330,7 @@ func MergeRecommendations(recommended []AIRecommendation, ranked []SearchResult,
 				ThumbnailURL:    item.ThumbnailURL,
 				PreviewVideoURL: item.PreviewVideoURL,
 				Source:          item.Source,
-				Reason:          GeminiFallbackReason,
+				Reason:          "Gemini 검토가 부족해 편집용 후보로 추가된 결과입니다.",
 				Recommended:     false,
 			})
 		}

backend/services/search_collectors.go

@@ -15,7 +15,7 @@ type searchCollector interface {
 type envatoCollector struct{}
 
 func (envatoCollector) Name() string    { return "Envato" }
-func (envatoCollector) MaxResults() int { return 10 }
+func (envatoCollector) MaxResults() int { return 12 }
 func (envatoCollector) Enabled(enabledPlatforms map[string]bool) bool {
 	return len(enabledPlatforms) == 0 || enabledPlatforms["envato"]
 }
@@ -31,7 +31,7 @@ func (envatoCollector) Enrich(searcher *SearchService, result SearchResult) Sear
 type artgridCollector struct{}
 
 func (artgridCollector) Name() string    { return "Artgrid" }
-func (artgridCollector) MaxResults() int { return 10 }
+func (artgridCollector) MaxResults() int { return 12 }
 func (artgridCollector) Enabled(enabledPlatforms map[string]bool) bool {
 	return len(enabledPlatforms) == 0 || enabledPlatforms["artgrid"]
 }

frontend/index.html

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