kiro cli autocomplete not working in antigravity terminal

### 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

macOS 26.5.0 (25F71)

### Expected behaviour

When starting to type, for example, "cd" or "git" inside a repo, auto-complete selection should appear.

### Actual behaviour

Nothing appears. Auto-complete is not working.

### Steps to reproduce

1. Open Antigravity and open any project.
2. Open the terminal.
3. Start typing. For example, "cd", "git" or "npm"
4. Type space
5. Nothing happen

### Environment

```yaml

[q-details]
version = "2.8.1"
hash = "43ca6648d9e72889f9b499548df52a230d216456"
date = "2026-06-17T23:47:37.987102Z (10h ago)"
variant = "full"

[system-info]
os = "macOS 26.5.0 (25F71)"
chip = "Apple M1 Pro"
total-cores = 10
memory = "32.00 GB"

[environment]
os = "Mac"
shell-path = "/bin/zsh"
shell-version = "5.9"
terminal = "VSCode"
install-method = "unknown"

[env-vars]
PATH = "/Users/USER/.rvm/gems/ruby-3.4.8/bin:/Users/USER/.rvm/gems/ruby-3.4.8@global/bin:/Users/USER/.rvm/rubies/ruby-3.4.8/bin:/Users/USER/.antigravity-ide/antigravity-ide/bin:/Users/USER/.antigravity/antigravity/bin:/Users/USER/.nvm/versions/node/v20.15.1/bin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/pkg/env/global/bin:/Library/Apple/usr/bin:/opt/homebrew/bin:/Users/USER/.rvm/gems/ruby-3.4.8/bin:/Users/USER/.rvm/gems/ruby-3.4.8@global/bin:/Users/USER/.rvm/rubies/ruby-3.4.8/bin:/Users/USER/.antigravity-ide/antigravity-ide/bin:/Users/USER/.antigravity/antigravity/bin:/Users/USER/.nvm/versions/node/v20.15.1/bin:/Users/USER/.local/bin:/Users/USER/Library/Android/sdk/emulator:/Users/USER/Library/Android/sdk/platform-tools:/Applications/Antigravity.app/Contents/Resources/app/bin:/Users/USER/.rvm/bin:/Users/USER/.antigravity-ide/extensions/vscjava.vscode-java-debug-0.59.0-universal/bundled/scripts/noConfigScripts:/Users/USER/Library/Android/sdk/emulator:/Users/USER/Library/Android/sdk/platform-tools:/Applications/Antigravity.app/Contents/Resources/app/bin:/Users/USER/.rvm/bin"
QTERM_SESSION_ID = "7bf0f3f0467b41a982cc8bd0260f13bd"
Q_SET_PARENT_CHECK = "1"
Q_TERM = "2.8.1"
SHELL = "/bin/zsh"
TERM = "xterm-256color"
ZDOTDIR = "/Users/USER"
__CFBundleIdentifier = "com.microsoft.VSCode"
```

Start by reproducing the issue in an Antigravity terminal using zsh, following the listed steps with commands such as `cd`, `git`, and `npm`; run `q doctor` and `q restart` as noted. Done means autocomplete selections appear after typing these commands and a space in a project terminal.

Written by the indexing model from the issue text.