surfer: Abstract naming and casing logic in model

[quirogas]

Currently, casing transformations (e.g., strcase.ToKebab, strcase.ToSnake) are performed at the last minute within the builder logic. This can lead to inconsistencies and makes the logic harder to trace.

Context & Rationale

• Maintainability: Scattered casing logic is fragile. If a naming convention changes, it must be updated in multiple places.
• Precedent: Reviewers noted this was a "mistake made in gen_sfc" and should be avoided by abstracting casing into the model.
• Sidekick vs Surfer: We need to determine if these transformations belong in the core sidekick/api model (affecting all generators) or a Surfer-specific internal model.

Implementation Considerations

• Evaluate if api.Field should expose a KebabName or SnakeName property.
• If modifying sidekick is not desired, ensure the Surfer internal model (see issue refactor(internal/python): replace command mocks and add GitHub action #3365) handles these transformations during the mapping phase.
• Audit all calls to strcase in internal/surfer/gcloud/builder.go.

Proposed Solution

• Research the impact of adding gcloud-specific naming properties to the sidekick API model.
• Alternatively, implement a transformation layer in Surfer that populates an internal model with pre-cased names.

Relevant files

• internal/surfer/gcloud/builder.go
• internal/sidekick/api/model.go