fix: Updated display format for asset currency dif (#12775)

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## **Description**
- This PR updates the format of the change in currency for negative
cases to be `-$123.45` instead of `$-123.45`

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also include relevant motivation and context. Have in mind the following
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## **Related issues**

Fixes: #10922 

## **Manual testing steps**

1. Go to Assets
2. Look at the amount changed in dollars
3.

## **Screenshots/Recordings**

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before and after of your change. -->

### **Before**

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### **After**
![Simulator Screenshot - iPhone 15 Pro Max - 2024-12-18 at 11 57
50](https://github.com/user-attachments/assets/df7fc031-2152-4f72-878e-4be41d0e0d0c)

![Screenshot_1734563249](https://github.com/user-attachments/assets/d713ddee-cfcf-4e68-b08c-566e448a12a1)

<!-- [screenshots/recordings] -->

## **Pre-merge author checklist**

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## **Pre-merge reviewer checklist**

- [ ] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
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app/util/number/index.js

@@ -482,6 +482,7 @@ export function addCurrencySymbol(
   currencyCode,
   extendDecimals = false,
 ) {
+  const prefix = parseFloat(amount) < 0 ? '-' : '';
   if (extendDecimals) {
     if (isNumberScientificNotationWhenString(amount)) {
       amount = amount.toFixed(18);
@@ -512,17 +513,22 @@ export function addCurrencySymbol(
     amount = parseFloat(amount).toFixed(2);
   }
 
+  const amountString = amount.toString();
+  const absAmountStr = amountString.startsWith('-')
+    ? amountString.slice(1) // Remove the first character if it's a '-'
+    : amountString;
+
   if (currencySymbols[currencyCode]) {
-    return `${currencySymbols[currencyCode]}${amount}`;
+    return `${prefix}${currencySymbols[currencyCode]}${absAmountStr}`;
   }
 
   const lowercaseCurrencyCode = currencyCode?.toLowerCase();
 
   if (currencySymbols[lowercaseCurrencyCode]) {
-    return `${currencySymbols[lowercaseCurrencyCode]}${amount}`;
+    return `${prefix}${currencySymbols[lowercaseCurrencyCode]}${absAmountStr}`;
   }
 
-  return `${amount} ${currencyCode}`;
+  return `${prefix}${absAmountStr} ${currencyCode}`;
 }
 
 /**