Update section title for code review instructions

Update README with xonsh code review and tracing tips

Document known performance issues on Windows

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Revise Xonsh and Windows section in README

Update README.md

Update README.md

Update README with subprocess handling in Xonsh

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Fix eval function call in README example

Add CLI tool section to README

Update README with 'jc' installation and usage

Document jc tool usage for command output formatting

Update README.md

Rename myproject to my and update key assignment