feat(fusion_accounting_bank_rec): migration audit PDF report

QWeb PDF showing per-company: backfilled precedent count, pattern count,
remaining unreconciled bank line count. Bound to fusion.migration.wizard
so it appears in the Print menu after migration runs.

- reports/migration_audit_report.py defines the AbstractModel
  report.fusion_accounting_bank_rec.migration_audit_template, which
  aggregates per-company counts from fusion.reconcile.precedent
  (source='backfill'), fusion.reconcile.pattern, and
  account.bank.statement.line (is_reconciled=False).
- reports/migration_audit_report_views.xml is the QWeb template.
- reports/migration_audit_report_action.xml registers the
  ir.actions.report bound to fusion.migration.wizard.

Made-with: Cursor

fusion_accounting_bank_rec/__manifest__.py

@@ -1,6 +1,6 @@
 {
     'name': 'Fusion Accounting — Bank Reconciliation',
-    'version': '19.0.1.0.21',
+    'version': '19.0.1.0.22',
     'category': 'Accounting/Accounting',
     'sequence': 28,
     'summary': 'Native V19 bank reconciliation widget with AI confidence scoring + behavioural learning.',
@@ -33,6 +33,8 @@ Built by Nexa Systems Inc.
         'data/cron.xml',
         'wizards/auto_reconcile_wizard_views.xml',
         'wizards/bulk_reconcile_wizard_views.xml',
+        'reports/migration_audit_report_views.xml',
+        'reports/migration_audit_report_action.xml',
     ],
     'assets': {
         'web.assets_backend': [