feat: implement LNURL payment handling in LNBits plugin

- Added a new function to handle LNURL payments, allowing users to send payments via LNURL addresses.
- Integrated LNURL payment processing into the existing sendCoins function, enhancing the wallet's capabilities for Lightning Network transactions.

packages/server/lib/plugins/wallet/lnbits/lnbits.js

@@ -131,12 +131,44 @@ async function getStatus(account, tx) {
   }
 }
 
+async function sendLNURL(account, lnurl, cryptoAtoms) {
+  validateConfig(account)
+  
+  const paymentData = {
+    lnurl: lnurl,
+    amount: parseInt(cryptoAtoms.toString()) * 1000, // Convert satoshis to millisatoshis
+    comment: `Lamassu ATM - ${new Date().toISOString()}`
+  }
+  
+  const endpoint = `${account.endpoint}/api/v1/payments/lnurl`
+  const result = await request(endpoint, 'POST', paymentData, account.adminKey)
+  
+  if (!result.payment_hash) {
+    throw new Error('LNBits LNURL payment failed: No payment hash returned')
+  }
+  
+  return {
+    txid: result.payment_hash,
+    fee: result.fee_msat ? Math.ceil(result.fee_msat / 1000) : 0
+  }
+}
+
 async function sendCoins(account, tx) {
   validateConfig(account)
   const { toAddress, cryptoAtoms, cryptoCode } = tx
   
   await checkCryptoCode(cryptoCode)
   
+  // Handle LNURL addresses
+  if (isLnurl(toAddress)) {
+    return sendLNURL(account, toAddress, cryptoAtoms)
+  }
+  
+  // Handle bolt11 invoices
+  if (!isLnInvoice(toAddress)) {
+    throw new Error('Invalid Lightning address: must be bolt11 invoice or LNURL')
+  }
+  
   const paymentData = {
     out: true,
     bolt11: toAddress