Add support for Redis 7 sharded Pub/Sub

[mp911de]

See https://redis.io/topics/pubsub#sharded-pubsub

For the Cluster Pub/Sub, we likely need to only consider keys for routing as Cluster Pub/Sub intentionally drops the slot hash calculation.

[Dmdl]

Do we know when will lettuce support sharded Pub/Sub?

[jthacker2]

want to use this as well, any plan for support?

[prashanth-srinivasan1]

@mp911de is there any plan to implement this in the near future?

[mp911de]

This feature requires a bit of design. While there is an intent to implement this, there's no time-line as this project is maintained in our spare time.

[adamsau]

any updates? @mp911de

[adamsau]

This feature requires a bit of design. While there is an intent to implement this, there's no time-line as this project is maintained in our spare time.

is it possible to submit a PR on this? any specific design decision we need to be aware? @mp911de

[mp911de]

Happy to review a pull request.

[tishun]

The sharded pub/sub should be handled by

• Add support for SSUBSCRIBE #2758
• Add support for SPUBLISH #2757
• Add support for SUNSUBSCRIBE #2759
• Add support for PUBSUB SHARDCHANNELS #2756
• Implement the PUBSUB SHARDNUMSUB command #2776

Duplicate of #2762