fix(audit): centraliser l'horloge UTC

app/time_utils.py

@@ -0,0 +1,19 @@
+"""Time helpers with explicit storage semantics.
+
+The deployed schema currently stores timestamps in ``DateTime`` columns
+without timezone information.  Until the real PostgreSQL schema is restored
+and migrated, application timestamps must therefore remain naive values.
+They are nevertheless generated from an aware UTC clock so the convention is
+explicit and does not rely on the deprecated :meth:`datetime.utcnow` API.
+"""
+
+from datetime import UTC, datetime
+
+
+def utc_now_naive() -> datetime:
+    """Return the current UTC instant without ``tzinfo`` for legacy columns.
+
+    Replace this compatibility boundary with aware UTC values when the
+    corresponding columns are migrated to timezone-aware types.
+    """
+    return datetime.now(UTC).replace(tzinfo=None)