[MM-43917] Cloud Freemium limits API: messages/posts (#20152)

* WIP - Add api and app funcs

* Add test cases

* Add utils testcases

* Exclude deleted posts

* Add doc for func

* Move api from cloud to usage

* Allow api access to authenticated users

* Change int to int64

* Fix lint issue

* Simplify err check

Co-authored-by: Ashish Bhate <ashish.bhate@mattermost.com>

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>
Co-authored-by: Ashish Bhate <ashish.bhate@mattermost.com>

api4/user_test.go

@@ -2102,7 +2102,7 @@ func TestPermanentDeleteAllUsers(t *testing.T) {
 		require.NoError(t, err)
 		require.Greater(t, len(users), 0)
 
-		postCount, err := th.App.Srv().Store.Post().AnalyticsPostCount("", false, false)
+		postCount, err := th.App.Srv().Store.Post().AnalyticsPostCount(&model.PostCountOptions{})
 		require.NoError(t, err)
 		require.Greater(t, postCount, int64(0))
 
@@ -2115,7 +2115,7 @@ func TestPermanentDeleteAllUsers(t *testing.T) {
 		require.NoError(t, err)
 		require.Len(t, users, 0)
 
-		postCount, err = th.App.Srv().Store.Post().AnalyticsPostCount("", false, false)
+		postCount, err = th.App.Srv().Store.Post().AnalyticsPostCount(&model.PostCountOptions{})
 		require.NoError(t, err)
 		require.Equal(t, postCount, int64(0))