feat: SEO backend data (1/4)

internal/infrastructure/useCases/auditFailures.go

@@ -24,6 +24,7 @@ type failureReason struct {
 
 var failureReasons = []failureReason{
 	{article.ErrInvalidTitle, "The title must be between 3 and 200 characters."},
+	{article.ErrSlugTaken, "That slug is already used by another article on this site."},
 	{image.ErrImageTypeNotAllowed, "The file must be a PNG, JPEG, WEBP or SVG image."},
 	{image.ErrImageTooLarge, "The file is too large to upload."},
 	{image.ErrImageUnreadable, "The image could not be read."},
@@ -63,6 +64,7 @@ var failureReasons = []failureReason{
 	{site.ErrSiteHasArticles, "The site still has articles."},
 	{site.ErrInvalidSiteURL, "The site address is not valid."},
 	{site.ErrInvalidLocale, "The locale is not valid."},
+	{site.ErrInvalidTitleTemplate, "The title template must contain %title%."},
 	{site.ErrUseSetDefault, "Use the default site action to change the default."},
 	{site.ErrInvalidReassign, "The destination site is not valid."},
 	{author.ErrSlugTaken, "That slug is already used by another author."},