watchBlock using a wss transport not emitting latest block when emitOnBegin is enabled

[Cygnusfear]

Check existing issues

• I checked there isn't already an issue for the bug I encountered.

Viem Version

2.21.0

Current Behavior

We're running into a case with watchBlocks using a wss transport not properly emitting the latest block when emitOnBegin is enabled. We're noticing this on an L3 Arbitrum chain with low tx volume, Arbitrum only generates new block as new TX come in.
Blocks are emitted as soon as a new TX/Block is made.

Expected Behavior

emitOnBegin always emits the latest available block on begin
(similar to how http would, or wss transport using polling)

Steps To Reproduce

import {
  createPublicClient,
  type Client,
  http,
  type Chain,
  webSocket,
} from "viem";
import { arbitrumSepolia as _arbitrumSepolia } from "viem/chains";

export const testConduit = Object.assign(_arbitrumSepolia as Chain, {
  name: "Conduit Cloudlines",
  id: 573146821555,
  blockExplorers: {
    default: {
      name: "Conduit",
      url: "https://explorer-cloudlines-7gm4rnga08.t.conduit.xyz",
    },
  },
  rpcUrls: {
    default: {
      http: ["https://rpc-cloudlines-7gm4rnga08.t.conduit.xyz"],
      webSocket: ["wss://rpc-cloudlines-7gm4rnga08.t.conduit.xyz"],
    },
  },
});

async function main() {
  const publicClient = await createPublicClient({
    transport: webSocket(testConduit.rpcUrls.default.webSocket[0]),
  });

  const publicClient2 = await createPublicClient({
    transport: http(testConduit.rpcUrls.default.http[0]),
  });

  const lastWssBlock = await publicClient.getBlock();
  const lastHttpBlock = await publicClient2.getBlock();

  console.log("lastWssBlock", lastWssBlock);
  console.log("lastHttpBlock", lastHttpBlock);

  publicClient.watchBlocks({
    emitOnBegin: true,
    onBlock: async (block) => {
      console.log("publicClient1: ", block);
    },
    pollingInterval: 1000,
  });

  publicClient2.watchBlocks({
    emitOnBegin: true,
    onBlock: async (block) => {
      console.log("publicClient2:", block);
    },
    pollingInterval: 1000,
  });
}

main().catch((err) => {
  console.error("mainLoop Err", err);
});

Link to Minimal Reproducible Example

https://gist.github.com/ya7ya/322444102d4b926c289148bc98973010

Anything else?

No response

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