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/Admin/General/FormatsController.php

@@ -0,0 +1,33 @@
+<?php
+
+namespace App\Http\Controllers\V1\Admin\General;
+
+use App\Http\Controllers\Controller;
+use App\Support\Formatters\DateFormatter;
+use App\Support\Formatters\TimeFormatter;
+use App\Support\Formatters\TimeZones;
+use Illuminate\Http\JsonResponse;
+
+class FormatsController extends Controller
+{
+    public function dateFormats(): JsonResponse
+    {
+        return response()->json([
+            'date_formats' => DateFormatter::get_list(),
+        ]);
+    }
+
+    public function timeFormats(): JsonResponse
+    {
+        return response()->json([
+            'time_formats' => TimeFormatter::get_list(),
+        ]);
+    }
+
+    public function timezones(): JsonResponse
+    {
+        return response()->json([
+            'time_zones' => TimeZones::get_list(),
+        ]);
+    }
+}