Fix JSON strings with quotes causing escaping issues (fixes #39)

[konard]

Summary

This PR fixes the issue where JSON strings containing quotes and special characters get corrupted when passed through command-stream's shell interpolation, making it impossible to reliably work with JSON data using shell commands.

🐛 Problem

JSON strings inherently contain quotes which conflict with shell quoting mechanisms:

• Nested quotes in JSON values break shell parsing
• Escaped quotes get double-escaped or mangled
• Special characters like backticks and dollar signs cause additional issues
• JSON structure gets broken, making it unparseable

✅ Solution

1. Enhanced Shell Operator Detection

• Added detection for redirection operators (>, >>, <, 2>, etc.)
• Commands with redirection now properly use real shell instead of virtual commands

2. Improved needsRealShell Function

• Added basic redirection operators to unsupported features list
• Forces JSON commands with redirection to use real shell execution

3. Virtual Command Bypass Logic

• Added needsRealShell check to prevent JSON redirection commands from using virtual echo
• Maintains backward compatibility for simple commands

🧪 Test Plan

• Added comprehensive JSON escaping test suite (tests/json-escaping.test.mjs)
• All existing tests pass with no regressions
• Manual testing with complex JSON scenarios
• File redirection scenarios work correctly
• Special characters (quotes, backticks, dollar signs) preserved

📝 Usage Examples

Before (Broken):

const jsonData = { name: "test", description: "with 'quotes' and \"double quotes\"" };
await $`echo '${JSON.stringify(jsonData)}' > config.json`; // Creates invalid JSON

After (Fixed):

const jsonData = { name: "test", description: "with 'quotes' and \"double quotes\"" };
await $`echo ${JSON.stringify(jsonData)} > config.json`; // Works correctly! ✅

📊 Impact

✅ Configuration management - Can now write JSON config files reliably
✅ Data processing - JSON data preserved during shell operations
✅ API integrations - JSON payloads can be passed through shell commands
✅ Build scripts - Package.json and similar files can be manipulated

🔄 Changes

• Enhanced shell operator detection in src/$.mjs
• Updated needsRealShell function in src/shell-parser.mjs
• Added virtual command bypass logic
• Bumped version to 0.7.2
• Added comprehensive test suite

🤖 Generated with Claude Code

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Resolves #39