Misspelled command parameters are silently ignored in playbooks

When a playbook command has a misspelled parameter (e.g. backgound instead of background), Pydantic silently drops the unknown key and the playbook runs with giving no error or warning.
The parser should reject unknown fields.

### Your environment
* Version of AttackMate (`attackmate --version`)
* Python version (`python --version`)
* Ansible, Docker, pip, or uv installation?
* OS and version

### Steps to reproduce
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### Playbook
Provide a minimal playbook that reproduces the issue (remove sensitive data):

```yaml

```

### Config
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```yaml

```

### Expected behaviour
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### Actual behaviour
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### Log output
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