feat(article): support regenerating failed articles

server/internal/tenant/app/template_service.go

@@ -349,11 +349,11 @@ func (s *TemplateService) Generate(ctx context.Context, templateID int64, req Ge
 			  AND template_id = $3
 			  AND source_type = 'template'
 			  AND deleted_at IS NULL
-			  AND generate_status = 'draft'
+			  AND generate_status IN ('draft', 'failed')
 			FOR UPDATE
 		`, *req.ArticleID, actor.TenantID, templateID).Scan(&articleID)
 		if err != nil {
-			return nil, response.ErrConflict(40913, "draft_not_editable", "draft is not editable")
+			return nil, response.ErrConflict(40913, "article_not_regeneratable", "article cannot be regenerated in its current state")
 		}
 		if err := updateGeneratedArticleState(ctx, tx, articleID, actor.TenantID, initialTitle, "generating", wizardStateJSON); err != nil {
 			return nil, fmt.Errorf("mark draft generating: %w", err)
@@ -536,7 +536,6 @@ func (s *TemplateService) executeGeneration(ctx context.Context, job generationJ
 
 	versionID, err := articleRepo.CreateArticleVersion(ctx, repository.CreateArticleVersionInput{
 		ArticleID:       job.ArticleID,
-		VersionNo:       1,
 		Title:           title,
 		HTMLContent:     "",
 		MarkdownContent: content,