feat: add negative topups (#2835)

* feat: add negative topups
* remove topup dialog

---------

Co-authored-by: Vlad Stan <stan.v.vlad@gmail.com>

lnbits/static/js/wallet.js

@@ -51,7 +51,6 @@ window.app = Vue.createApp({
       balance: parseInt(wallet.balance_msat / 1000),
       fiatBalance: 0,
       mobileSimple: false,
-      credit: 0,
       update: {
         name: null,
         currency: null
@@ -151,6 +150,9 @@ window.app = Vue.createApp({
         this.receive.paymentHash = null
       }
     },
+    handleBalanceUpdate(value) {
+      this.balance = this.balance + value
+    },
     createInvoice() {
       this.receive.status = 'loading'
       if (LNBITS_DENOMINATION != 'sats') {