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/main/java/dev/lions/unionflow/server/exception/GlobalExceptionMapper.java

@@ -3,6 +3,7 @@ package dev.lions.unionflow.server.exception;
 import dev.lions.unionflow.server.service.SystemLoggingService;
 import jakarta.inject.Inject;
 import jakarta.ws.rs.ForbiddenException;
+import jakarta.ws.rs.NotAllowedException;
 import jakarta.ws.rs.NotAuthorizedException;
 import jakarta.ws.rs.NotFoundException;
 import jakarta.ws.rs.WebApplicationException;
@@ -64,6 +65,8 @@ public class GlobalExceptionMapper implements ExceptionMapper<Throwable> {
         String stacktrace = getStackTrace(exception);
 
         // Persister dans system_logs (ne pas laisser ça crasher le mapper)
+        // Note: systemLoggingService est @Transactional → ne peut pas être appelé depuis
+        // le thread IO de Vert.x (ex: exceptions levées avant le dispatch vers worker thread)
         try {
             systemLoggingService.logError(
                     determineSource(exception),
@@ -74,6 +77,10 @@ public class GlobalExceptionMapper implements ExceptionMapper<Throwable> {
                     "/" + endpoint,
                     statusCode
             );
+        } catch (IllegalStateException e) {
+            // BlockingOperationNotAllowedException est une IllegalStateException :
+            // le mapper est appelé depuis le thread IO, on ne peut pas démarrer une transaction JTA.
+            log.debug("Cannot persist error log from IO thread ({}): {}", e.getClass().getSimpleName(), message);
         } catch (Exception e) {
             log.warn("Failed to log error to system_logs", e);
         }
@@ -90,7 +97,8 @@ public class GlobalExceptionMapper implements ExceptionMapper<Throwable> {
     private boolean isExpectedClientError(Throwable exception) {
         return exception instanceof NotFoundException
                 || exception instanceof ForbiddenException
-                || exception instanceof NotAuthorizedException;
+                || exception instanceof NotAuthorizedException
+                || exception instanceof NotAllowedException;
     }
 
     private int determineStatusCode(Throwable exception) {