feat: read BusProNet base data from the MyE&P API

migrations/Version20260813120000.php

@@ -0,0 +1,49 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+/**
+ * Moves destination.country from the raw BusProNet abbreviations to lowercase ISO-2.
+ *
+ * The column used to hold whatever BusProNet reported as hotel/land, lowercased: a,
+ * ch, d, f, i, nl. That set is not a standard - the same country appears as A, AT and
+ * AUT upstream - so the import now stores the ISO code MyE&P resolves instead, and the
+ * existing rows are converted to match. The flag icons and the country filters use the
+ * same vocabulary and are switched with it.
+ */
+final class Version20260813120000 extends AbstractMigration
+{
+    private const TO_ISO = [
+        'a' => 'at',
+        'd' => 'de',
+        'f' => 'fr',
+        'i' => 'it',
+    ];
+
+    public function getDescription(): string
+    {
+        return 'Convert destination.country to lowercase ISO-3166-1 alpha-2';
+    }
+
+    public function up(Schema $schema): void
+    {
+        foreach (self::TO_ISO as $legacy => $iso) {
+            $this->addSql('UPDATE destination SET country = ? WHERE country = ?', [$iso, $legacy]);
+        }
+
+        // ch and nl are already ISO; empty strings were never a country
+        $this->addSql("UPDATE destination SET country = NULL WHERE country = ''");
+    }
+
+    public function down(Schema $schema): void
+    {
+        foreach (self::TO_ISO as $legacy => $iso) {
+            $this->addSql('UPDATE destination SET country = ? WHERE country = ?', [$legacy, $iso]);
+        }
+    }
+}