feat: improve sharding types and utils

[weboko]

Description

Our type definitions for sharding are hectic and utilities are spear across the codebase.

Examples:

• https://github.com/waku-org/js-waku/blob/c7682ea67c54d2c26a68ce96208003fb1ffc915c/packages/interfaces/src/message.ts#L3C1-L10C2
• https://github.com/waku-org/js-waku/blob/c7682ea67c54d2c26a68ce96208003fb1ffc915c/packages/interfaces/src/waku.ts#L18
• https://github.com/waku-org/js-waku/blob/master/packages/interfaces/src/sharding.ts
• https://github.com/waku-org/js-waku/blob/c7682ea67c54d2c26a68ce96208003fb1ffc915c/packages/interfaces/src/protocols.ts#L19
• and utilities https://github.com/waku-org/js-waku/blob/master/packages/utils/src/common/sharding/index.ts
• ShardReader entity in ConnectionManager

Solution

We should ensure we have one place for types and definitions are clear with no ambiguity:

• shard / shards / number of shards under cluster
• auto sharding vs static sharding

As for utils everything should be moved into ShardingReader and re-used from there if possible.

[weboko]

#2471 made area better, right now seems this proposal doesn't make much sense