Neokil fix/csharp test type name collision

[wing328]

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Summary by cubic

Fixes model name collisions in generated C# Generic Host API tests and corrects response type flags (array/map/free-form) in codegen. Adds patches for Elm, Protobuf schema, and WSDL generators to keep object response handling consistent.

• Bug Fixes
  • In csharp/libraries/generichost/api_test.mustache, Assert.IsType<> now prefixes model return types with {{packageName}}.{{modelPackage}} (only when isModel) to avoid ambiguous references.
  • In DefaultCodegen.fromResponse, properly sets isArray, isMap, isModel, and isFreeFormObject for response schemas and preserves container metadata.
  • In ElmClientCodegen, ProtobufSchemaCodegen, and WsdlSchemaCodegen, override fromResponse to set object response flags and container info, restoring prior behavior for object responses.
  • Updated tests and samples: added a C# unit test to verify map response flags; expanded Java CXF tests to cover array/map responses; regenerated C# Generic Host samples across latest, net8, net10, net4.7, and net4.8.

^{Written for commit 3c8cb92. Summary will update on new commits.}