MM-59932: Migrate remaining caches to Redis (#27880)

- We introduce 2 new APIs:
1. Scan: this allows incremental iteration
without blocking the Redis server and is the
recommended way to iterate over keys. With this,
we have entirely removed the need for Keys.
2. RemoveMulti: this allows deletion of multiple
keys in a single operation which optimizes
network round trips.

- While here, we make a small improvement to
GetStatusFromCache, where we remove the shallow
copy which wasn't necessary because we always
serialize the data from the cache.
- We do not use Redis for session cache because of
frequent requests to iterate the entire cache which leads
to a lot of `SCAN` calls.
- Avoid broadcasting status update messages for Redis case.
- Setting cache expiry for status cache
- Removing .Set method altogether to prevent
any chances of setting an item with no expiry.

https://mattermost.atlassian.net/browse/MM-59932

```release-note
NONE
```

server/channels/app/platform/cluster_handlers.go

@@ -60,7 +60,7 @@ func (ps *PlatformService) ClusterUpdateStatusHandler(msg *model.ClusterMessage)
 		ps.logger.Warn("Failed to decode status from JSON")
 	}
 
-	ps.statusCache.Set(status.UserId, status)
+	ps.statusCache.SetWithDefaultExpiry(status.UserId, status)
 }
 
 func (ps *PlatformService) ClusterInvalidateAllCachesHandler(msg *model.ClusterMessage) {
@@ -128,7 +128,7 @@ func (ps *PlatformService) InvalidateAllCachesSkipSend() {
 func (ps *PlatformService) InvalidateAllCaches() *model.AppError {
 	ps.InvalidateAllCachesSkipSend()
 
-	if ps.clusterIFace != nil {
+	if ps.clusterIFace != nil && *ps.Config().CacheSettings.CacheType == model.CacheTypeLRU {
 		msg := &model.ClusterMessage{
 			Event:            model.ClusterEventInvalidateAllCaches,
 			SendType:         model.ClusterSendReliable,