Provide Support for KMP

[Anolcera]

Right now Stream Chat works great on Android, but the networking part isn’t supported in a shared Kotlin Multiplatform module. That makes it hard to use in projects that target both Android and iOS with shared logic.

Since more and more teams are moving to KMP for real production apps, having official support for Stream Chat in shared code (not just Android) would be a big deal. It would mean we could reuse the same SDK for things like channel and message APIs without writing separate iOS implementations or building our own bridges.

Any plans to add proper KMP support? Even an early version or limited subset of functionality would already make a huge difference.