feat(ctrl): PSBT signing for BTC via sats-connect (V3 flow)

[towanTG]

Summary

• Splits the CTRL UTXO case so Bitcoin wires a proper PSBT signer via CTRL's sats-connect `sign_psbt` RPC
• Passes the signer into `getUtxoToolbox(Chain.Bitcoin, { signer })` so the toolbox can synthesize `signAndBroadcastTransaction` — unblocking the V3 SwapKit swap plugin for CTRL BTC
• BCH/DOGE/LTC keep the existing bespoke `walletTransfer` path (CTRL only supports sats-connect for BTC)

Context

The V3 SwapKit plugin calls `wallet.signAndBroadcastTransaction(psbtTransaction)`. That method is synthesized by `getUtxoToolbox` only when a `{ signer }` is passed at construction. CTRL's current BTC path calls `getUtxoToolbox(chain)` with no signer and only overrides `transfer`, so the plugin's V3 path breaks. This PR matches the pattern already used by Phantom / OKX / BITGET / ONEKEY / PASSKEYS.

Notes

• `provider.request` is invoked with a promise-and-callback wrapper (the existing `transaction()` helper uses callback form; `getCtrlAddress` awaits it as a promise — we tolerate both shapes)
• PSBT is base64 in and out (CTRL docs: `sign_psbt` with `{ psbt, signInputs, allowedSignHash, broadcast }`)

Test plan

• Connect CTRL wallet, verify BTC address returned
• Run a V3 BTC swap end-to-end; confirm `signAndBroadcastTransaction` resolves with a txid
• Regression: legacy `wallet.transfer({...})` for BTC still works
• Regression: BCH/DOGE/LTC via CTRL unchanged

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