Add an immutable property.Value type for the Go SDK

Add an immutable property.Value type for the Go SDK: a task in MiMo-V2.6-RL-harbor-code: MiMo-V2.6-RL Code (Harbor) (Harbor dataset). We want a clean, self-contained representation of a Pulumi property value that we can grow into a replacement for the sprawling resource.PropertyValue . Please add…

The task

We want a clean, self-contained representation of a Pulumi property value that we can grow into a replacement for the sprawling `resource.PropertyValue`. Please add a new package, importable as `github.com/pulumi/pulumi/sdk/v3/go/property`, that exposes an immutable `Value` type.

Part of FineEnvs/MiMo-V2.6-RL-harbor-code.