bugfix: proper quote parsing in subCommands.ts

[B44ken]

see #270150

a "proper" fix would be introducing tree-sitter but this is straightforward and fixes the motivating example below

curl 'https://example.com/api?bool&detail=7&other=3' '{"key1":"value1","key2":"value2"}'

[Copilot]

Pull Request Overview

This PR fixes quote parsing in subCommands.ts to properly handle shell commands containing quoted strings with special characters. The implementation introduces proper quote-aware parsing to prevent incorrect command splitting when quotes are present.

• Replaces simple string splitting with a character-by-character parser that respects quoted strings
• Adds support for backslash escaping and nested subshell extraction
• Updates test cases to cover realistic scenarios including curl commands with quoted URLs and JSON data

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/vs/workbench/contrib/terminalContrib/chatAgentTools/browser/subCommands.ts	Implements quote-aware parsing logic with escape handling and subshell extraction
src/vs/workbench/contrib/terminalContrib/chatAgentTools/test/browser/subCommands.test.ts	Adds comprehensive test cases for subshells and realistic curl command scenarios

[jere-mie]

LGTM 🚀