feat: merge lead-region cascade to main — deals-city + rossvyaz normalize, prod-parity verified

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/tests/Unit/Support/DaDataRegionMapTest.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Support\DaDataRegionMap;
+use App\Support\RussianRegions;
+
+it('maps exact official names via RussianRegions', function (): void {
+    expect(DaDataRegionMap::toSubjectCode('Москва'))->toBe(82)
+        ->and(DaDataRegionMap::toSubjectCode('Московская область'))->toBe(56)
+        ->and(DaDataRegionMap::toSubjectCode('Санкт-Петербург'))->toBe(83)
+        ->and(DaDataRegionMap::toSubjectCode('Ленинградская область'))->toBe(53);
+});
+
+it('trims surrounding whitespace before mapping', function (): void {
+    expect(DaDataRegionMap::toSubjectCode('  Москва  '))->toBe(82);
+});
+
+it('flags ambiguous agglomeration strings', function (): void {
+    expect(DaDataRegionMap::isAmbiguous('Санкт-Петербург и область'))->toBeTrue()
+        ->and(DaDataRegionMap::isAmbiguous('Москва и область'))->toBeTrue()
+        ->and(DaDataRegionMap::isAmbiguous('Москва'))->toBeFalse()
+        ->and(DaDataRegionMap::isAmbiguous('Санкт-Петербург'))->toBeFalse();
+});
+
+it('returns null for unmappable region', function (): void {
+    expect(DaDataRegionMap::toSubjectCode('Атлантида'))->toBeNull()
+        ->and(DaDataRegionMap::toSubjectCode(''))->toBeNull();
+});
+
+it('resolves all 89 RussianRegions names', function (): void {
+    foreach (RussianRegions::CODE_TO_NAME as $code => $name) {
+        expect(DaDataRegionMap::toSubjectCode($name))->toBe($code);
+    }
+});