derjanb/hamiyoca ? reverse-engineered prompt

Build me a simple Bitcoin mining demo that I can run locally in the browser.

I want a page that starts mining when I call begin_mining(), and it should support running the work in plain JavaScript, a WebWorker, and WebGL if available. Use a small PHP app so I can serve it with PHP’s built in server, and make it easy to plug in my local bitcoind details in one config file. The main goal is to show a working “hash me if you can” style miner with a clean demo page, basic UI feedback, and the core SHA256 mining logic wired up.

If you need to check anything, look up current browser and PHP docs online. Keep it simple and runnable from localhost with clear instructions in the app itself.