Requesting either a --no-stream flag or a buffered output mode in 2.0. The old version printed faster. The new version is more visually disruptive

### 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 6.6.87.2-microsoft-standard-WSL2 - Ubuntu 22.04.5 LTS

### Expected behaviour

Chat responses should either render instantly (buffered until complete) or provide a configuration option to control streaming output. The previous kiro-cli 1.x rendered responses noticeably faster and was easier to read.

### Actual behaviour

In kiro-cli 2.0.0, chat responses render token-by-token as they stream from the model. The output scrolls too slowly to feel instant but too fast to actually read along with, resulting in a poor reading experience. There is no config command, --no-stream flag, or any setting to control this behaviour. --classic seems to help a little bit but then you lose the new TUI, which looks nice and creates more readable breaks and divisions (when not actively printing)

### Steps to reproduce

1. Install kiro-cli 2.0.0
2. Run kiro-cli chat
3. Ask any question that produces a multi-paragraph response
4. Observe the token-by-token rendering — text scrolls continuously at an awkward pace that is difficult to follow
5. Run kiro-cli chat --help — no streaming-related options exist

### Environment

```yaml

[q-details]
version = "2.0.0"
hash = "0026b0505ef7bc2b10780c7bdb57813e5d949747"
date = "2026-04-13T09:03:52.798806Z (1d ago)"
variant = "minimal"

[system-info]
chip = "13th Gen Intel(R) Core(TM) i7-1355U"
total-cores = 6
memory = "15.44 GB"

[system-info.os.linux]
kernel_version = "6.6.87.2-microsoft-standard-WSL2"
id = "ubuntu"
name = "Ubuntu"
pretty_name = "Ubuntu 22.04.5 LTS"
version_id = "22.04"
version = "22.04.5 LTS (Jammy Jellyfish)"

[environment]
cwd = "/home/USER"
cli-path = "/home/USER"
os = "Linux"
shell-path = "/usr/bin/bash"
shell-version = "5.1.16"
install-method = "unknown"
in-wsl = true

[env-vars]
DISPLAY = ":0"
PATH = "/home/USER/.nvm/versions/node/v24.14.0/bin:/home/USER/bin:/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:/usr/lib/wsl/lib:/mnt/c/Python313/Scripts/:/mnt/c/Python313/:/mnt/c/WINDOWS/system32:/mnt/c/WINDOWS:/mnt/c/WINDOWS/System32/Wbem:/mnt/c/WINDOWS/System32/WindowsPowerShell/v1.0/:/mnt/c/WINDOWS/System32/OpenSSH/:/mnt/c/Program Files/PuTTY/:/mnt/c/Program Files/nodejs/:/mnt/c/ProgramData/chocolatey/bin:/mnt/c/Program Files/Amazon/AWSCLIV2/:/mnt/c/Program Files/Docker/Docker/resources/bin:/mnt/c/Users/connellybr/AppData/Local/VanDyke Software/Clients/:/mnt/c/Users/connellybr/AppData/Local/VanDyke Software/SecureFX/:/mnt/c/Users/connellybr/AppData/Local/Microsoft/WindowsApps:/mnt/c/Users/connellybr/AppData/Local/Programs/Git/cmd:/mnt/c/Users/connellybr/AppData/Local/Programs/Git/mingw64/bin:/mnt/c/Users/connellybr/AppData/Local/Programs/Git/usr/bin:/mnt/c/Users/connellybr/AppData/Local/Programs/Microsoft VS Code/bin:/mnt/c/bin:/mnt/c/Users/connellybr/AppData/Roaming/npm:/mnt/c/Users/connellybr/AppData/Local/GitHubDesktop/bin:/mnt/c/Users/connellybr/AppData/Local/Programs/Kiro/bin:/snap/bin:/home/USER/.local/bin:/home/USER/.local/bin:/home/USER/bin"
QTERM_SESSION_ID = "caf891fa643f4be0a5fea1d53fc5440e"
Q_SET_PARENT_CHECK = "1"
Q_TERM = "1.26.1"
SHELL = "/bin/bash"
TERM = "xterm-256color"
```