Create a morphir-ir-json project which defines JsonCodecs for the Morphir IR.

[DamianReeves]

The Codec's Encoder, Decoder, and its combination Codec should support taking an implicit CodecOptions object which for one should allow us to target handling specific versions of the Morphir IR JSON serialization targets.

We should start by supporting encoding and decoding as morphir-elm does.

We should encode according to how morphir-elm does it.

The morphir-elm codebase defines Codecs for its JSON pieces.

The morphir.ir.json files that are produced by the morphir-elm tooling is a serialized version of the PackageDefinition.

The Codec for PackageDefinition can be found here: https://github.com/finos/morphir-elm/blob/9122b99a6f500af389bfa26c2f7c604ea64485c2/src/Morphir/IR/Package/CodecV1.elm

For reference on how Elm approaches Json encoding see: https://package.elm-lang.org/packages/elm/json/latest/Json-Encode