Reorganize Admin/General: 14 controllers down to 6

Move global reference data to SuperAdmin:
- CountriesController, CurrenciesController (not company-scoped)

Merge exchange rate operations into ExchangeRateProviderController:
- GetAllUsedCurrenciesController -> usedCurrenciesWithoutRate()
- BulkExchangeRateController -> bulkUpdate()

Consolidate single-action controllers:
- DateFormatsController + TimeFormatsController + TimezonesController -> FormatsController
- NextNumberController + NumberPlaceholdersController -> SerialNumberController
- SearchUsersController merged into SearchController::users()

app/Http/Controllers/V1/SuperAdmin/CurrenciesController.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace App\Http\Controllers\V1\SuperAdmin;
+
+use App\Http\Controllers\Controller;
+use App\Http\Resources\CurrencyResource;
+use App\Models\Currency;
+use Illuminate\Http\Request;
+use Illuminate\Http\Response;
+
+class CurrenciesController extends Controller
+{
+    /**
+     * Handle the incoming request.
+     *
+     * @return Response
+     */
+    public function __invoke(Request $request)
+    {
+        $currencies = Currency::latest()->get();
+
+        return CurrencyResource::collection($currencies);
+    }
+}