Phase 0 : entités, migrations, API Platform, PostGIS

- API Platform + Doctrine ORM + jsor/doctrine-postgis installés
- 6 entités Symfony (SargassumObservation, SargassumForecast,
  DataIngestionJob, CoastalPoint, ImpactScore, UserFeedback)
- Migration initiale manuelle avec CREATE EXTENSION postgis,
  toutes les tables, index GIST et BTREE
- doctrine.yaml configuré pour PostgreSQL 16 + types PostGIS
- Roadmap Phase 0 complète

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/config/packages/doctrine.yaml

@@ -0,0 +1,53 @@
+doctrine:
+    dbal:
+        url: '%env(resolve:DATABASE_URL)%'
+        server_version: '16'
+        profiling_collect_backtrace: '%kernel.debug%'
+        use_savepoints: true
+        types:
+            geometry:   Jsor\Doctrine\PostGIS\Types\GeometryType
+            geography:  Jsor\Doctrine\PostGIS\Types\GeographyType
+    orm:
+        auto_generate_proxy_classes: true
+        enable_lazy_ghost_objects: true
+        report_fields_where_declared: true
+        validate_xml_mapping: true
+        naming_strategy: doctrine.orm.naming_strategy.underscore_number_aware
+        identity_generation_preferences:
+            Doctrine\DBAL\Platforms\PostgreSQLPlatform: identity
+        auto_mapping: true
+        mappings:
+            App:
+                type: attribute
+                is_bundle: false
+                dir: '%kernel.project_dir%/src/Entity'
+                prefix: 'App\Entity'
+                alias: App
+        controller_resolver:
+            auto_mapping: false
+
+when@test:
+    doctrine:
+        dbal:
+            # "TEST_TOKEN" is typically set by ParaTest
+            dbname_suffix: '_test%env(default::TEST_TOKEN)%'
+
+when@prod:
+    doctrine:
+        orm:
+            auto_generate_proxy_classes: false
+            proxy_dir: '%kernel.build_dir%/doctrine/orm/Proxies'
+            query_cache_driver:
+                type: pool
+                pool: doctrine.system_cache_pool
+            result_cache_driver:
+                type: pool
+                pool: doctrine.result_cache_pool
+
+    framework:
+        cache:
+            pools:
+                doctrine.result_cache_pool:
+                    adapter: cache.app
+                doctrine.system_cache_pool:
+                    adapter: cache.system