refactor: introduce EnumVarMap for improved enum handling across code generators

[Mattias-Sehlstedt]

Introduces a enum wrapper model that collects the common operations that are done when creating an enum variable.

This is done as a HashMap wrapper rather than a Codegen model since we want to retain the easy extension of the data. This structure mimics the already existing XMap models that are within the model folder.

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Summary by cubic

Introduces EnumVarMap to standardize and type-safe enum handling across generators, moving enum constants off CodegenConstants and replacing getEnumVarsAsString with getEnumVars. Refactor spans multiple generators with no changes to generated outputs.

• Refactors

  • Added EnumVarMap (HashMap wrapper) with helpers and ENUM_* constants.
  • Switched enum flows to List<EnumVarMap> in core (buildEnumVars, post-processing, extension updates).
  • Removed EnumUtils.getEnumVarsAsString; updated generators to EnumUtils.getEnumVars (C#, Dart, F#, PHP, Python incl. Pydantic V1, Java/Helidon, Go, Nim, OCaml, Haskell, Crystal, Ruby, TypeScript Fetch, Avro, Protobuf, etc.).
  • Protobuf: migrated to EnumVarMap, added enum indexes; tests updated to assert boolean isString.

• Migration

  • Signatures now use List<EnumVarMap>:
    • buildEnumVars(List<Object>, String) returns List<EnumVarMap>.
    • updateEnumVarsWithExtensions(...) accepts List<EnumVarMap>.
  • Replace CodegenConstants.ENUM_* with EnumVarMap.ENUM_*.
  • Replace EnumUtils.getEnumVarsAsString(...) with EnumUtils.getEnumVars(...).
  • When mutating enum vars, use EnumVarMap methods: enumVar(...), setEnumName(...), setEnumValue(...), isString(boolean), getEnumName(), getEnumValue(), isString().

^{Written for commit 889607d. Summary will update on new commits.}

[cubic-dev-ai]

All reported issues were addressed across 30 files

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