feat: import points côtiers depuis OpenStreetMap (Overpass API)

backend/migrations/Version20260409000000.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20260409000000 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Ajoute osm_id sur coastal_point pour idempotence import OSM';
+    }
+
+    public function up(Schema $schema): void
+    {
+        $this->addSql('ALTER TABLE coastal_point ADD osm_id VARCHAR(30) DEFAULT NULL');
+        $this->addSql('CREATE UNIQUE INDEX uniq_coastal_osm_id ON coastal_point (osm_id)');
+    }
+
+    public function down(Schema $schema): void
+    {
+        $this->addSql('DROP INDEX uniq_coastal_osm_id');
+        $this->addSql('ALTER TABLE coastal_point DROP COLUMN osm_id');
+    }
+}