frontend: polish app launch and release experience

neode-ui/src/components/ReceiveBitcoinModal.vue

@@ -39,6 +39,7 @@
           </div>
           <div v-else class="mb-3 text-center">
             <p class="text-white/50 text-sm mb-2">{{ t('web5.generateFreshAddress') }}</p>
+            <p v-if="processing" class="text-xs text-white/40">Checking Lightning wallet readiness...</p>
           </div>
         </div>
 
@@ -67,6 +68,7 @@ import { ref, nextTick } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { rpcClient } from '@/api/rpc-client'
 import BaseModal from '@/components/BaseModal.vue'
+import { explainReceiveAddressFailure } from '@/utils/bitcoinReceive'
 
 const { t } = useI18n()
 
@@ -124,6 +126,9 @@ async function receive() {
       nextTick(() => renderQr(res.payment_request, lightningQrCanvas.value, 'lightning:'))
     } else if (receiveMethod.value === 'onchain') {
       const res = await rpcClient.call<{ address: string }>({ method: 'lnd.newaddress' })
+      if (!res.address) {
+        throw new Error('LND did not return a Bitcoin address')
+      }
       onchainAddress.value = res.address
       nextTick(() => renderQr(res.address, onchainQrCanvas.value, 'bitcoin:'))
     } else {
@@ -136,7 +141,9 @@ async function receive() {
       emit('received')
     }
   } catch (err: unknown) {
-    error.value = err instanceof Error ? err.message : 'Failed'
+    error.value = receiveMethod.value === 'onchain'
+      ? explainReceiveAddressFailure(err)
+      : err instanceof Error ? err.message : 'Failed'
   } finally {
     processing.value = false
   }