Cluster fix READWRITE command

Problem: The replica knows nothing about the cluster and always works in read-only mode. It means we can read from the replica all the data but don't get a -MOVE error if we try to write something.

Expected behavior: In READONLY mode we return -MOVE if we don't have the key or for any WRITE command. In READWRITE mode we return -MOVE error for any READ/WRITE commands

If we want to support this we will need to save in connection cntx a boolean set it if readonly command was invaded, and on cluster mode before invoking transaction read commands we need to check if this flag was set.
Where to start:
Service::VerifyCommandState() and IsUserAllowedToInvokeCommandGeneric

add
```
if (!IsClusterEmulated()) {
return cmd_cntx.rb->SendError(kClusterDisabled);
```

Start with Service::VerifyCommandState() and IsUserAllowedToInvokeCommandGeneric, then trace the connection context and cluster-mode command checks. Confirm the READONLY and READWRITE behaviors described in the issue, including the -MOVE responses, and verify the cluster-disabled path shown in the issue.

Written by the indexing model from the issue text.