feat: BackupService real pg_dump, OrganisationService region stats, SystemConfigService overrides

- BackupService: DB-persisted metadata (BackupRecord/BackupConfig entities + V16 Flyway migration),
  real pg_dump execution via ProcessBuilder, soft-delete on deleteBackup, pg_restore manual guidance
- OrganisationService: repartitionRegion now queries Adresse entities (was Map.of() stub)
- SystemConfigService: in-memory config overrides via AtomicReference (no DB dependency)
- SystemMetricsService: null-guard on MemoryMXBean in getSystemStatus() (fixes test NPE)
- Souscription workflow: SouscriptionService, SouscriptionResource, FormuleAbonnementRepository,
  V11 Flyway migration, admin REST clients
- Flyway V8-V15: notes membres, types référence, type orga constraint, seed roles,
  première connexion, Wave checkout URL, Wave telephone column length fix
- .gitignore: added uploads/ and .claude/

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

src/test/java/dev/lions/unionflow/server/entity/SouscriptionOrganisationBranchTest.java

@@ -1,6 +1,7 @@
 package dev.lions.unionflow.server.entity;
 
 import dev.lions.unionflow.server.api.enums.abonnement.StatutSouscription;
+import dev.lions.unionflow.server.api.enums.abonnement.StatutValidationSouscription;
 import dev.lions.unionflow.server.api.enums.abonnement.TypePeriodeAbonnement;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
@@ -47,6 +48,24 @@ class SouscriptionOrganisationBranchTest {
         assertThat(s.getQuotaUtilise()).isEqualTo(0);
     }
 
+    /**
+     * Branch manquante : statutValidation == null → la valeur par défaut EN_ATTENTE_PAIEMENT est affectée.
+     */
+    @Test
+    @DisplayName("onCreate: statutValidation null → initialisé à EN_ATTENTE_PAIEMENT")
+    void onCreate_statutValidationNull_setsDefault() throws Exception {
+        SouscriptionOrganisation s = new SouscriptionOrganisation();
+        s.setDateDebut(LocalDate.now());
+        s.setDateFin(LocalDate.now().plusMonths(1));
+        s.setStatutValidation(null); // forcer null pour couvrir le then-branch de L168
+
+        Method onCreate = SouscriptionOrganisation.class.getDeclaredMethod("onCreate");
+        onCreate.setAccessible(true);
+        onCreate.invoke(s);
+
+        assertThat(s.getStatutValidation()).isEqualTo(StatutValidationSouscription.EN_ATTENTE_PAIEMENT);
+    }
+
     // ── decrementerQuota() ────────────────────────────────────────────────────
 
     /**