MM-35396 Refactor GetThreadForUser store func to take membership as argument to prevent replica lag issues and reduce joins in query (#17754)

* Update store function GetThreadForUser to use master DB to fix replica lag

* Refactor GetThreadForUser store func to take membership as argument to prevent replica lag issues and reduce joins in query

* Add translation

* Fix test

* Updates per feedback

* Minor clean-up per feedback

api4/post_test.go

@@ -2621,7 +2621,9 @@ func TestSetPostUnreadWithoutCollapsedThreads(t *testing.T) {
 		//  MentionCountRoot should be zero so that supported clients don't show the channel as unread
 		require.Equal(t, channelUnread.MsgCountRoot, int64(0))
 
-		thread, err := th.App.GetThreadForUser(th.BasicUser.Id, th.BasicTeam.Id, rootPost1.Id, false)
+		threadMembership, err := th.App.GetThreadMembershipForUser(th.BasicUser.Id, rootPost1.Id)
+		require.Nil(t, err)
+		thread, err := th.App.GetThreadForUser(th.BasicTeam.Id, threadMembership, false)
 		require.Nil(t, err)
 		require.Equal(t, int64(2), thread.UnreadMentions)
 		require.Equal(t, int64(3), thread.UnreadReplies)

api4/user.go

@@ -2871,15 +2871,21 @@ func getThreadForUser(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	extendedStr := r.URL.Query().Get("extended")
-
 	extended, _ := strconv.ParseBool(extendedStr)
-	threads, err := c.App.GetThreadForUser(c.Params.UserId, c.Params.TeamId, c.Params.ThreadId, extended)
+
+	threadMembership, err := c.App.GetThreadMembershipForUser(c.Params.UserId, c.Params.ThreadId)
 	if err != nil {
 		c.Err = err
 		return
 	}
 
-	w.Write([]byte(threads.ToJson()))
+	thread, err := c.App.GetThreadForUser(c.Params.TeamId, threadMembership, extended)
+	if err != nil {
+		c.Err = err
+		return
+	}
+
+	w.Write([]byte(thread.ToJson()))
 }
 
 func getThreadsForUser(c *Context, w http.ResponseWriter, r *http.Request) {