feat: add mapping functions

internal/author/controller.go

@@ -1,4 +1,4 @@
-package user
+package author
 
 import (
 	"strconv"
@@ -23,7 +23,7 @@ func (u *Controller) ListAuthors(c *gin.Context) {
 		c.AbortWithError(500, err)
 		return
 	}
-	c.JSON(200, authors)
+	c.JSON(200, toAuthorSlice(authors))
 }
 
 func (u *Controller) GetAuthorByID(c *gin.Context) {
@@ -39,5 +39,5 @@ func (u *Controller) GetAuthorByID(c *gin.Context) {
 		return
 	}
 
-	c.JSON(200, author)
+	c.JSON(200, toAuthor(author))
 }