fix(Accounts): Avoid model reset on every account change

This fixes the issues where the accounts model gets reset on every minor model change triggering full UI refresh.
This is not fixing the root cause, but the symptoms in the upper-most level I could find in order to keep the regression risk to a low level.

src/app/modules/main/wallet_section/accounts/model.nim

@@ -1,4 +1,4 @@
-import NimQml, Tables, strutils, stew/shims/strformat
+import NimQml, Tables, strutils, stew/shims/strformat, std/sequtils
 
 import ./item
 import ../../../shared_models/currency_amount
@@ -75,11 +75,55 @@ QtObject:
       ModelRole.CanSend.int: "canSend"
     }.toTable
 
+  proc removeItemWithIndex(self: Model, index: int) =
+    if (index < 0 or index >= self.items.len):
+      return
+    let parentModelIndex = newQModelIndex()
+    defer: parentModelIndex.delete
+    self.beginRemoveRows(parentModelIndex, index, index)
+    self.items.delete(index)
+    self.endRemoveRows()
+
+  proc insertItem(self: Model, item: Item, index: int) =
+    if (index < 0 or index > self.items.len):
+      return
+    let parentModelIndex = newQModelIndex()
+    defer: parentModelIndex.delete
+    self.beginInsertRows(parentModelIndex, index, index)
+    self.items.insert(item, index)
+    self.endInsertRows()
+
+  proc findAccountIndex(self: Model, account: Item): int =
+    for i in 0 ..< self.items.len:
+      if self.items[i].address() == account.address():
+        return i
+    return -1
 
   proc setItems*(self: Model, items: seq[Item]) =
-    self.beginResetModel()
-    self.items = items
-    self.endResetModel()
+    var indexesToRemove: seq[int]
+
+    #remove
+    for i in 0 ..< self.items.len:
+      if not items.anyIt(it.address() == self.items[i].address()):
+        indexesToRemove.add(i)
+
+    while indexesToRemove.len > 0:
+      let index = pop(indexesToRemove)
+      self.removeItemWithIndex(index)
+
+    # Update or insert
+    for i in 0 ..< items.len:
+      var account = items[i]
+      let index = self.findAccountIndex(account)
+      if index >= 0:
+        let qIndex = self.createIndex(i, 0, nil)
+        defer: qIndex.delete
+
+        self.items[index] = account
+        self.dataChanged(qIndex, qIndex)
+        continue
+      self.insertItem(account, i)
+      
     self.countChanged()
 
     for item in items: