fix: change webpack dev server port to avoid websocket conflict

[Einstellung]

Problem:
When running the demo prover-ts on macOS, encountered error:
"Invalid WebSocket frame: RSV1 must be clear"

Investigation:

• Several other macOS developers have reported this issue
• Found relevant discussions and similar cases
• You can find detailed discussions at: websockets issues

Solution:
Based on the solutions shared in the discussions:

• Changed webpack-dev-server port from 8080 to 3000
• Successfully resolved the WebSocket connection issue

[heeckhau]

Hey @Einstellung, thanks for your PR!

I suspect there’s another process running on your computer that’s already serving HTTP data on port 8080. Your workaround of running the Prover demo on a different port is a great idea. However, port 3000 is also frequently used (e.g., for React applications). I suggest we choose a less commonly used default port instead, such as 3456. What do you think?

[heeckhau]

Can you use a different port than 3000?

[Einstellung]

Sorry, I previously shared the wrong link regarding my problem.

Here is the correct link

As you can see, this is not a rare issue specific to my Mac, but rather a common problem that occasionally occurs on other Mac system as well.

I've already adjusted port to 3456, and it's now working fine on my Mac.

[heeckhau]

Thanks!