eth_subscribe RPC method returns 16-character subscription ID instead of 32-byte ID

[krisbitney]

Description

Recently, there was a change to the behavior of eth_subscribe. It is now returning a 16-character subscription ID (e.g. TlCPBeW4fku7BlSo) instead of a 32-byte ID.

I believe the changes in this PR may be related: #1504

Steps to Reproduce

        const result = (await client.transport.request({
          method: "eth_subscribe",
          params: ["newHeads"],
        })) as any

Expected vs. Actual Behavior

The expected behavior would be to receive a 32-byte hex string representing the subscription ID. The actual received value is a 16-character string, which presumably is a UTF-8 encoded representation of the 32-byte ID.

Environment

TypeScript with Viem