bug: Q CLI applies improper formatting when _ is included in the output

### Checks

- [x] I have searched [github.com/aws/amazon-q-developer-cli/issues](https://github.com/aws/amazon-q-developer-cli/issues?q=) and there are no duplicates of my issue
- [x] I have run `q doctor` in the affected terminal session
- [x] I have run `q restart` and replicated the issue again

### Operating system

AL2

### Expected behaviour

output does not show italics when a single _ is in the output, if its not meant to be in italics. I assume the output is being markdown formatted, the AI probably needs to be instructed to escape these characters if it doesn't want markdown format?

### Actual behaviour

output shows in italics after a single _ is included in the output, and the _ is excluded

### Steps to reproduce

see screenshot

### Environment

```yaml
[q-details]
version = "1.12.7"
hash = "ed77799a52644ba49a3ed76b15c25cd9334c4b8d"
date = "2025-07-22T17:40:04.719028Z (3d ago)"
variant = "minimal"

[system-info]
chip = "Intel(R) Xeon(R) Platinum 8175M CPU @ 2.50GHz"
total-cores = 8
memory = "61.35 GB"

[system-info.os.linux]
kernel_version = "5.10.238-215.956.amzn2int.x86_64"
id = "amzn"
name = "Amazon Linux"
pretty_name = "Amazon Linux 2"
version_id = "2"
version = "2"
variant = "internal"

[environment]
cwd = "redacted"
cli-path = "redacted"
os = "Linux"
shell-path = "redacted"
shell-version = "5.8"
install-method = "toolbox"
in-ssh = true

[env-vars]
PATH = "redacted"
SHELL = "/bin/zsh"
TERM = "xterm-256color"
```

Inizia riproducendo il problema nella q CLI usando un output contenente un singolo carattere di sottolineatura, quindi segui il percorso di formattazione dell’output del terminale. Verifica che i caratteri di sottolineatura letterali rimangano visibili e non attivino il corsivo, e aggiungi o aggiorna la copertura per questo comportamento se viene individuata la posizione di test pertinente.

Scritto dal modello di indicizzazione a partire dal testo della issue.