chore: add AGENTS.md for opencode agents

# Agents

This role installs and configures Zabbix Web (frontend) with Apache.

## Role Analysis

- **Type**: Monitoring infrastructure role (web UI)

- **OS Support**: Debian 12

- **Deployment Method**: Direct (package installation)

- **Scope**: Zabbix web frontend installation and configuration

## Key Variables

| Variable | Default | Description |

|----------|---------|-------------|

| `zabbix_web_name` | `Siempie Monitoring` | Web UI title |

| `zabbix_server_db_name` | `zabbix` | Database name |

| `zabbix_server_db_user` | `zabbix` | Database user |

| `zabbix_server_db_pass` | `zabbixpass` | Database password |

## Testing

```bash

ansible-lint

molecule test

```