fix: resolve merge conflicts with main branch

Merge origin/main into feature branch, resolving 3 conflicts:
- app/api/__init__.py: add classification_rules_router alongside new
  routers from main (audit_logs, i18n, mobile, compliance, translation)
- app/models.py: keep ClassificationRuleModel alongside new models from
  main (MobileDevice, ComplianceTemplate, PipelineRoutingRule)
- tests/conftest.py: import both ClassificationRuleModel and new models
  from main (AuditLog, ComplianceTemplate)

Also renumber migration from 027 to 037 to chain from the latest
migration on main (036_add_document_translation_fields).

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

mobile/app/(auth)/_layout.tsx

@@ -0,0 +1,17 @@
+/**
+ * Layout for the unauthenticated route group: Welcome → Login.
+ *
+ * Uses a headerless native stack so the screens animate naturally.
+ */
+
+import { Stack } from "expo-router";
+import React from "react";
+
+export default function AuthLayout() {
+  return (
+    <Stack screenOptions={{ headerShown: false }}>
+      <Stack.Screen name="index" />
+      <Stack.Screen name="login" />
+    </Stack>
+  );
+}