[FEATURE] Add windowsHide option for hooks on Windows

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

When hooks execute on Windows, a CMD console window briefly appears for each hook execution. This creates a poor user experience, especially with hooks like Stop that run after every response

Proposed Solution

Attempted Workarounds (all failed)

1. PowerShell -WindowStyle Hidden - window still flashes
2. VBScript wrapper with WshShell.Run ..., 0, True - window still flashes
3. Batch file with start /b - window still flashes

The root cause is that Claude Code uses child_process to spawn hook commands, which creates a visible cmd.exe window on Windows before the actual command runs.

## Proposed Solution
Add a windowsHide option for hooks (similar to what was added in SDK v0.17.1 - see #103 in claude-agent-sdk-typescript).

Example configuration:
```json
{
"hooks": {
"Stop": [{
"hooks": [{
"type": "command",
"command": "node script.js",
"windowsHide": true
}]
}]
}
}

Or default windowsHide: true for all hook executions on Windows

Alternative Solutions

_No response_

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_