QCLI crashes after using MCP server tool

### 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 15.4.0 (24E248)

### Expected behaviour

The MCP server's tool was invoked by QCLI with incorrect arguments Afterwards QCLI crashed and QCLI cannot be used for any future prompts. QCLI should be able to continue serving new prompts.

### Actual behaviour

The MCP server's tool was invoked by QCLI with incorrect arguments Afterwards QCLI crashed and QCLI cannot be used for any future prompts. QCLI should be able to continue serving new prompts.

### Steps to reproduce

Set up instruction:
1. set up [aws-documentation-mcp-server](https://github.com/awslabs/mcp/tree/main/src/aws-documentation-mcp-server) on QCLI
2. query for "find the latest anthropic model version on bedrock"
3. after tool validation fails, Q crashes and any further user prompts to QCLI will have the same error

more details here: https://quip-amazon.com/bSYqAFy8IfAM/Bug-for-MCP-in-QCLI

### Environment

```yaml
[q-details]
version = "1.9.1"
hash = "5d2c2807cab9bc6c9dc5fcd05f92c7a979e8a4f7"
date = "2025-04-29T06:22:42.917989Z (3d ago)"
variant = "full"

[system-info]
os = "macOS 15.4.0 (24E248)"
chip = "Apple M2 Pro"
total-cores = 12
memory = "32.00 GB"

[environment]
cwd = "/Users/USER"
cli-path = "/Users/USER"
os = "Mac"
shell-path = "/bin/zsh"
shell-version = "5.9"
terminal = "macOS"
install-method = "unknown"

[env-vars]
PATH = "/Users/USER/.toolbox/bin:/Users/USER/.local/share/mise/installs/python/3.12/bin:/Users/USER/.local/share/mise/installs/python/3.11/bin:/Users/USER/.local/share/mise/installs/python/3.10/bin:/Users/USER/.local/share/mise/installs/python/3.9/bin:/Users/USER/.local/share/mise/installs/python/3.8/bin:/opt/homebrew/bin:/opt/homebrew/sbin:/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:/Users/USER/.local/bin:/Applications/Visual Studio Code.app/Contents/Resources/app/bin:/Users/USER/.toolbox/bin"
QTERM_SESSION_ID = "b3c053688e48442a8fc868aeed4873b4"
Q_SET_PARENT_CHECK = "1"
Q_TERM = "1.9.1"
SHELL = "/bin/zsh"
TERM = "xterm-256color"
__CFBundleIdentifier = "com.apple.Terminal"
```

Inizia riproducendo il flusso di aws-documentation-mcp-server dal prompt di QCLI usando q doctor e q restart, quindi acquisisci il fallimento della convalida dello strumento e il comportamento in caso di crash. Il lavoro è completato quando un’invocazione non valida di uno strumento MCP viene gestita senza lasciare QCLI inutilizzabile e un prompt successivo ha esito positivo.

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