Replace exception getMessage() exposure with generic error messages
to prevent internal information disclosure. Errors are now logged
with full details while clients receive sanitized responses.
Affected endpoints:
- add_comment, update_comment, delete_comment
- update_ticket, export_tickets
- generate_api_key, revoke_api_key
- manage_templates, manage_workflows, manage_recurring
- custom_fields, get_users
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>