What problems was I solving

The @architect/codecs package contained a Json codec helper that was added alongside other custom codecs but never adopted by any caller, leaving dead code to maintain and an unused public export.

What user-facing changes did I ship

None — this is a pure dead-code cleanup with no visible behavior, API contract, or persisted-state changes.

How I implemented it

I deleted architect/codecs/main/json.ts, removed its barrel re-export from architect/codecs/main/index.ts, and regenerated/synced tools/typecheck/typecheck-manifest.generated.json so the deleted file is no longer passed to the typecheck boundary. I also verified with repo-wide greps that nothing imported Json from @architect/codecs.

Description for the changelog

Removed the unused Json codec from @architect/codecs along with its barrel re-export and generated typecheck manifest entry. The codec had no internal consumers, so this only reduces the package's public API surface and removes the corresponding source file.