#65 API: Delete Tenant

Implement endpoint to delete a tenant (soft delete). Endpoint: DELETE /api/v1/tenants/{tenant_id} Query Parameters: - hard_delete: Permanently delete (default: false, system_admin only) Response: Confirmation with deletion timestamp Required Permissions: system_admin only Implementation Requirements: - Soft delete by default (mark as deleted, retain data) - Hard delete requires explicit confirmation - Terminate all active sessions - Revoke all API keys - Archive audit logs before hard delete - 30-day recovery window for soft delete - Notify all tenant users via email Security: - Cannot delete tenant with active workflows (must force) - Require MFA confirmation for hard delete With ultra attention to details and correctness. Before closing: write comment summarizing implementation with screenshot.