Extension host unresponsive on Linux Mint 22 - kiro.kiroAgent freezes at startup, browser auth never opens

### 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

Linux 6.17.0-22-generic - Linux Mint 22.3

### Expected behaviour

Clicking "Sign in" should open the default browser (Firefox) to complete authentication, then return to Kiro IDE logged in.

### Actual behaviour

The extension host (kiro.kiroAgent) becomes unresponsive ~6 seconds after startup, before any user interaction. The "We will take you to your browser" screen appears but no browser opens. Kiro freezes completely and requires force shutdown. Running with --disable-gpu reduces severity but does not fix the issue.

### Steps to reproduce

1. Install Kiro IDE 0.11.133 on Linux Mint 22.3 (Zena) via .deb package
2. Launch Kiro from terminal: kiro
3. The sign-in screen appears
4. Click any sign-in button (GitHub, Google, etc.)
5. Screen shows "We will take you to your browser" but nothing happens
6. Extension host becomes unresponsive after ~6 seconds (visible in logs)

Note: xdg-open works correctly. kiro-cli is authenticated. IPv6 is unavailable on this network but IPv4 works fine.

### Environment

```yaml

[q-details]
version = "2.1.1"
hash = "1d2ba18834ea4e6a88312b0dc70b2014b703aa6e"
date = "2026-04-25T00:26:23.098938Z (24h ago)"
variant = "full"

[system-info]
chip = "Intel(R) Celeron(R) N4020 CPU @ 1.10GHz"
total-cores = 2
memory = "3.64 GB"

[system-info.os.linux]
kernel_version = "6.17.0-22-generic"
id = "linuxmint"
name = "Linux Mint"
pretty_name = "Linux Mint 22.3"
version_id = "22.3"
version = "22.3 (Zena)"

[environment]
cwd = "/home/USER"
cli-path = "/home/USER"
os = "Linux"
shell-path = "/usr/bin/bash"
shell-version = "5.2.21"
terminal = "Xfce Terminal"
install-method = "unknown"

[env-vars]
DISPLAY = ":0.0"
PATH = "/home/USER/.nvm/versions/node/v24.14.0/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin"
SHELL = "/bin/bash"
TERM = "xterm-256color"
XDG_CURRENT_DESKTOP = "XFCE"
XDG_SESSION_DESKTOP = "xfce"
XDG_SESSION_TYPE = "x11"
```