There's a minor style issue (double blank line at 191+193 after the JSG_REQUIRE removal), but clang-format handles whitespace in this repo, so that's not actionable.

This PR is a clean dead-code removal. It removes the isFiddle() plumbing from ThreadContext and IoContext, removes fiddle-specific code paths in the Cache API, Blob/FormData (the kj::Array<kj::byte> variant and parseWithoutLock), and sockets, and updates stale comments. All references to fiddle are fully eliminated from the source tree. The OneOf types in Blob are correctly narrowed. No behavioral changes for production code, no backward compatibility concerns, no security issues.

LGTM

github run

The generated output of @cloudflare/workers-types matches the snapshot in types/generated-snapshot 🎉