Track proposal for namespace-based generated types file splitting

[nac5504]

Description

Track the public proposal and review discussion for opt-in namespace-based file splitting of generated Types.swift output.

Related PRs:

• Add namespace-based types file splitting #925 implements the initial namespace-based splitting support (approved).
• [Generator][Experimental] Add opt-in dependency-aware sharded Types generation #866 contains related prior discussion and proposal context.

The intended proposal scope is limited to the implementation in #925:

• Add an opt-in namespace file-splitting strategy for generated types.
• Keep default generation unchanged: one Types.swift file.
• When enabled, emit:
  • Types.swift for root declarations
  • Types+Components.swift for the generated Components namespace
  • Types+Operations.swift for the generated Operations namespace
• Keep generated adopter-facing API names unchanged.
• Leave more advanced sharding strategies, such as dependency-aware or count-based splitting, to future proposals if benchmarks justify the added complexity.

Additional information

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