BLE One-Page: Build → Sign (ESP32) → Broadcast

全流程在一个页面：浏览器通过 BLE 连接 ESP32，把 Solana message 发过去签名，再把签名后的 tx 广播。

1) Connect BLE

Device: (not connected)

2) Build transaction message

From 默认读取 localStorage 的 wallet address（也可手动改）。

From (fee payer) base58

To base58

Amount (SOL)

recentBlockhash

Message (base64url)

3) Signed tx (from ESP32)

ESP32 返回的是 signed_tx_b64url，可以直接用于广播。

signed_tx_b64url

I confirm to broadcast

Status

(waiting)

Debug (BLE lines)

(none)