v8.0 module release (#22975)

https://mattermost.atlassian.net/browse/MM-52079

```release-note
We upgrade the module version to 8.0. The new module path is github.com/mattermost-server/server/v8.
```


Co-authored-by: Doug Lauder <wiggin77@warpmail.net>

server/model/channel_stats.go

@@ -0,0 +1,24 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package model
+
+type ChannelStats struct {
+	ChannelId       string `json:"channel_id"`
+	MemberCount     int64  `json:"member_count"`
+	GuestCount      int64  `json:"guest_count"`
+	PinnedPostCount int64  `json:"pinnedpost_count"`
+	FilesCount      int64  `json:"files_count"`
+}
+
+func (o *ChannelStats) MemberCount_() float64 {
+	return float64(o.MemberCount)
+}
+
+func (o *ChannelStats) GuestCount_() float64 {
+	return float64(o.GuestCount)
+}
+
+func (o *ChannelStats) PinnedPostCount_() float64 {
+	return float64(o.PinnedPostCount)
+}