[.NET] Fix the things schema for schema registry

[timtay-microsoft]

As seen here before the recent DTDL -> WoT conversion, the behavior of the schema registry generated classes was to define error types like

        [JsonPropertyName("error")]
        [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingDefault)]
        public SchemaRegistryError? Error { get; set; } = default;

But recent WoT changes made the same fields get defined like

        [JsonPropertyName("getError")]
        [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingDefault)]
        public SchemaRegistryError? GetError { get; set; } = default;

which would break deserialization of errors sent from the schema registry service.

This change alters the SchemaNames.json file such that running code gen gives the expected output on fields like the above. Then codegen was run on this branch.

See also #1229 for this same SchemaNames.json file change since it is needed in Rust as well.

[Copilot]

Pull request overview

Adjusts the WoT schema naming rules for Schema Registry so generated .NET response types deserialize service error payloads correctly (restoring the pre-WoT behavior where the error field is named error).

Changes:

• Update Schema Registry SchemaNames.json to emit the action response error field name as error.
• Regenerate/update .NET Schema Registry response schemas to use [JsonPropertyName("error")] and an Error property.
• Update the generated Schema Registry client stub logic to read/write the new Error property.

Reviewed changes

Copilot reviewed 1 out of 4 changed files in this pull request and generated no comments.

File	Description
eng/wot/schemaregistry/SchemaNames.json	Changes action response error field naming rule to output error.
dotnet/src/Azure.Iot.Operations.Services/SchemaRegistry/Generated/SchemaRegistry.g.cs	Updates generated client logic to set/check Response.Error instead of action-specific error properties.
dotnet/src/Azure.Iot.Operations.Services/SchemaRegistry/Generated/PutResponseSchema.g.cs	Renames error field mapping to [JsonPropertyName("error")] with Error property.
dotnet/src/Azure.Iot.Operations.Services/SchemaRegistry/Generated/GetResponseSchema.g.cs	Renames error field mapping to [JsonPropertyName("error")] with Error property.