fix(http-server-js): send bytes body directly without JSON serialization

[snipd-mikel]

When an operation returns a bytes body with a custom @header contentType
(e.g. "application/zip"), the emitter was unconditionally overwriting the
content-type with "application/json" and calling the non-existent
Uint8Array.toJsonObject(), causing a runtime crash.

Add a isStdType(body.type, "bytes") check in emitResultProcessingForType
before the JSON serialization path — mirroring the equivalent check already
present on the request deserialization side (added in #6898) — so that binary
responses are written directly to the response stream with the content-type
already set by the @header property.

Fixes #10609

[snipd-mikel]

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[snipd-mikel]

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