feat: support signing multiple transactions without reload

[mablr]

forge script support enabled by #15 and foundry-rs/foundry#12952 is great! However, now the current limiting factor is the webapp UX when signing multiple transactions. After signing a transaction, the app displays the receipt and requires a page reload and wallet reconnection to sign the next tx request generated by the script.

I guess the root cause is that pendingTx state persists after a successful signature/send

foundry-browser-wallet/src/App.tsx

Lines 148 to 187 in 94fd5b9

	// Sign and send the current pending transaction.
	const signAndSendCurrentTx = async () => {
	if (!selected || !pendingTx?.request) return;
	const walletClient = createWalletClient({
	transport: custom(selected.provider),
	chain: chain ?? undefined,
	});
	try {
	const hash = (await selected.provider.request({
	method: "eth_sendTransaction",
	params: [pendingTx.request],
	})) as `0x${string}`;
	setLastTxHash(hash);
	await api("/api/transaction/response", "POST", { id: pendingTx.id, hash, error: null });
	const receipt = await waitForTransactionReceipt(walletClient, { hash });
	setLastTxReceipt(receipt);
	} catch (e: unknown) {
	const msg =
	typeof e === "object" &&
	e &&
	"message" in e &&
	typeof (e as { message?: unknown }).message === "string"
	? (e as { message: string }).message
	: String(e);
	console.error("send failed:", msg);
	try {
	await api("/api/transaction/response", "POST", {
	id: pendingTx.id,
	hash: null,
	error: msg,
	});
	} catch {}
	}
	};

which prevents the polling from restarting. I think we need a way to clear completed request and resume polling for the next request.

I would be happy to contribute, lmk wdyt!