fix: technical debts left by the Sites, Authors and SEO slices, plus backend support for the new Sites and Authors pagination

internal/domain/site/siteRepositoryInterface.go

@@ -1,7 +1,19 @@
 package site
 
+type ListQuery struct {
+	Q    string
+	Page int
+	Size int
+}
+
+type Page struct {
+	Items []Site
+	Total int
+}
+
 type Repository interface {
 	List() ([]Site, error)
+	Find(query ListQuery) (Page, error)
 	Get(id uint32) (Site, error)
 	GetByKey(key string) (Site, error)
 	GetDefault() (Site, error)