Replaces Enterprise's l10n_ca_reports with Fusion-native equivalents:
- ca_balance_sheet, ca_profit_loss as fusion.report definitions
- fusion.tax.return model for GST/HST/PST/T4/T5018 filing tracking
- Auto-installs when l10n_ca + fusion_accounting_reports both present
Removes Westin's last Canadian-compliance dependency on Enterprise's
account_reports.
Made-with: Cursor
