MM-31063: Change constants to use CamelCase (#16608)

* MM-31063: Change constants to use CamelCase

* store package

* change allcaps to camel case (#16615)

* New tools.mod

Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

api4/post.go

@@ -253,7 +253,7 @@ func getPostsForChannelAroundLastUnread(c *Context, w http.ResponseWriter, r *ht
 			return
 		}
 
-		postList, err = c.App.GetPostsPage(model.GetPostsOptions{ChannelId: channelId, Page: app.PAGE_DEFAULT, PerPage: c.Params.LimitBefore, SkipFetchThreads: skipFetchThreads})
+		postList, err = c.App.GetPostsPage(model.GetPostsOptions{ChannelId: channelId, Page: app.PageDefault, PerPage: c.Params.LimitBefore, SkipFetchThreads: skipFetchThreads})
 		if err != nil {
 			c.Err = err
 			return