Payslips: format amounts in the org currency

/api/v1/me/payslips items and /api/v1/me/profile now carry the org base
currency. Payslip and Profile read it; the payslips screen formats with
the payslip currency, else the last profile's, else INR. INR output is
unchanged (rupee sign, lakh grouping, no decimals); other currencies show
the ISO code with their own minor units (AED 1,234.50, BHD 1,234.500).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

test/widget_test.dart

@@ -1,30 +0,0 @@
-// This is a basic Flutter widget test.
-//
-// To perform an interaction with a widget in your test, use the WidgetTester
-// utility in the flutter_test package. For example, you can send tap and scroll
-// gestures. You can also use WidgetTester to find child widgets in the widget
-// tree, read text, and verify that the values of widget properties are correct.
-
-import 'package:flutter/material.dart';
-import 'package:flutter_test/flutter_test.dart';
-
-import 'package:scalar_attendance/main.dart';
-
-void main() {
-  testWidgets('Counter increments smoke test', (WidgetTester tester) async {
-    // Build our app and trigger a frame.
-    await tester.pumpWidget(const MyApp());
-
-    // Verify that our counter starts at 0.
-    expect(find.text('0'), findsOneWidget);
-    expect(find.text('1'), findsNothing);
-
-    // Tap the '+' icon and trigger a frame.
-    await tester.tap(find.byIcon(Icons.add));
-    await tester.pump();
-
-    // Verify that our counter has incremented.
-    expect(find.text('0'), findsNothing);
-    expect(find.text('1'), findsOneWidget);
-  });
-}