disconnect() is missing on the mock client

disconnect() is missing on the mock client: a task in MiMo-V2.6-RL-harbor-code: MiMo-V2.6-RL Code (Harbor) (Harbor dataset). I'm using ioredis-mock as a drop-in replacement for ioredis in my test suite. My application code creates a Redis client, does its work, and then calls .disconnect() on it…

The task

I'm using `ioredis-mock` as a drop-in replacement for `ioredis` in my test suite. My application code creates a Redis client, does its work, and then calls `.disconnect()` on it during cleanup. Pretty standard pattern.

Part of FineEnvs/MiMo-V2.6-RL-harbor-code.