Inspection: implicitly inferred type for the hierarchy with multiple serializable types should be specified explicitly

[qwwdfsad]

Consider the following code (from our own guide):

@Serializable
sealed class Project {
    abstract val name: String
}
            
@Serializable
class OwnedProject(override val name: String, val owner: String) : Project()

fun main() {
    val data = OwnedProject("kotlinx.coroutines", "kotlin")
    println(Json.encodeToString(data))
} 

Json.encodeToString(data) is inferred by the compiler into Json.encodeToString<OwnedProject>(data) and it's not clear whether this is a intended behaviour (OwnedProject is serialized as a regular type) or a bug, and it was implied that OwnedProject should be serialized as a polymorphic type with type discriminator.
To avoid that, Json.encodeToString<Project>(data) should be used instead.

The proposal is to always warn about such call-sites with the quickfix that suggests specifying type explicitly. For polymorphic hierarchies, it would be nice if the quickfix was suggesting to use <BaseType> by default, as it's much easier to find out how to prevent type discriminator from appearing, rather than find out why it's not appearing in the final JSON

[sandwwraith]

See also #1247