Multipart generated enum case naming is inconsistent (other vs additionalProperties)

[czechboy0]

Description

The generated code doesn't follow the multipart SOAR proposal, see details in #596

Reproduction

See the example in #596.

Package version(s)

On main.

Expected behavior

Consistent behavior that matches the proposal.

Environment

Xcode 16 Beta.

Additional information

No response

[czechboy0]

Just fixing this would lead to a breaking change, so we'll need a feature flag here.

[simonjbeaumont]

Can we use a computed property or indirect enum case for the backwards compatibility?

[czechboy0]

For constructing the enum, possibly (including a typealias as well, for any potential inlined type), but consuming the enum, I don't think we can add a case without breaking people's code. But it's an idea we should explore.