Proposed rule: don't use `hashCode` in the item key for Lazy* Composables

[yogurtearl]

Proposed rule: don't use hashCode in the item key for Lazy* Composables

Item key should be unique.

.hashCode() is not unique.

e.g. these all have the same hash code, even on JS, WASM, etc, same hashcode is unlikely, but not impossible in the wild.

println("aaaa".hashCode())
println("aabB".hashCode())
println("aac#".hashCode())
println("bBaa".hashCode())
println("bBbB".hashCode())
println("c#aa".hashCode())
println("c#bB".hashCode())
println("c#c#".hashCode())

[ZacSweers]

PR welcome!