feat(showcase): 去掉 Bento 灵感类型，只保留 hero / work

后端校验、分组、后台列表，以及后台页面与首页取图都只认
hero 和 work；启动时清掉遗留的 bento 记录。

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

backend/internal/bootstrap/app.go

@@ -72,6 +72,10 @@ func NewApp(ctx context.Context) (*App, error) {
 	if err := db.WithContext(ctx).Exec(`ALTER TABLE model_configs DROP COLUMN IF EXISTS enabled`).Error; err != nil {
 		return nil, fmt.Errorf("drop model_configs.enabled: %w", err)
 	}
+	// 首页展示位不再支持 bento，清掉遗留记录。
+	if err := db.WithContext(ctx).Exec(`DELETE FROM showcase_items WHERE kind = 'bento'`).Error; err != nil {
+		return nil, fmt.Errorf("purge bento showcase: %w", err)
+	}
 	if err := seedDefaults(ctx, db); err != nil {
 		return nil, fmt.Errorf("seed defaults: %w", err)
 	}

backend/internal/http/handler/showcase.go

@@ -46,16 +46,16 @@ func (h *ShowcaseHandler) List(c *gin.Context) {
 
 // AdminList is the paginated flat view for the admin 首页内容 page — the public
 // List keeps its grouped shape for the home page, this one adds kind filter +
-// limit/offset/total. Order mirrors the old client flattening: hero → bento → work.
+// limit/offset/total. Order mirrors the old client flattening: hero → work.
 func (h *ShowcaseHandler) AdminList(c *gin.Context) {
 	grouped, err := h.showcase.Grouped(c.Request.Context())
 	if err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"detail": "failed to load showcase"})
 		return
 	}
-	kindFilter := c.Query("kind") // "" | hero | bento | work
+	kindFilter := c.Query("kind") // "" | hero | work
 	flat := make([]gin.H, 0, 16)
-	for _, kind := range []string{"hero", "bento", "work"} {
+	for _, kind := range []string{"hero", "work"} {
 		if kindFilter != "" && kind != kindFilter {
 			continue
 		}

backend/internal/repo/showcase_repo.go

@@ -62,9 +62,8 @@ func (r *ShowcaseRepository) Grouped(ctx context.Context) (map[string][]model.Sh
 	}
 
 	grouped := map[string][]model.ShowcaseItem{
-		"hero":  {},
-		"bento": {},
-		"work":  {},
+		"hero": {},
+		"work": {},
 	}
 	for _, item := range items {
 		grouped[item.Kind] = append(grouped[item.Kind], item)

backend/internal/service/admin_write.go

@@ -292,7 +292,7 @@ func (s *AdminWriteService) DeleteUserAPIKey(ctx context.Context, userID, keyID
 func (s *AdminWriteService) CreateShowcase(ctx context.Context, body map[string]any) (*model.ShowcaseItem, error) {
 	kind := normalizedShowcaseKind(stringValue(body["kind"]))
 	if kind == "" {
-		return nil, errors.New("kind must be hero, bento or work")
+		return nil, errors.New("kind must be hero or work")
 	}
 	image := strings.TrimSpace(stringValue(body["image"]))
 	if image == "" {
@@ -333,7 +333,7 @@ func (s *AdminWriteService) UpdateShowcase(ctx context.Context, entryID string,
 	if _, ok := body["kind"]; ok {
 		kind := normalizedShowcaseKind(stringValue(body["kind"]))
 		if kind == "" {
-			return nil, errors.New("kind must be hero, bento or work")
+			return nil, errors.New("kind must be hero or work")
 		}
 		patch["kind"] = kind
 	}
@@ -581,7 +581,7 @@ func normalizedStatus(status string) string {
 
 func normalizedShowcaseKind(kind string) string {
 	switch strings.TrimSpace(kind) {
-	case "hero", "bento", "work":
+	case "hero", "work":
 		return strings.TrimSpace(kind)
 	default:
 		return ""