#13 dev

• chore: updated gitignore
• feat: list command defaults to show open issues only
• feat: improved decoration on outputs

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Summary by cubic

Improve CLI readability with colorized output and bold help headers. list now shows only open issues by default, with filters for closed or all issues; CI now runs CodeQL scanning.

• New Features

  • list: defaults to open; add --all and --closed; colored IDs and state labels.
  • Output: colorized success, warnings, and neutral messages across commands; honors NO_COLOR.
  • Help/UI: bold section titles in --help; added .issues/ to .gitignore.

• Dependencies

  • Added github.com/fatih/color (plus github.com/mattn/go-colorable, github.com/mattn/go-isatty, golang.org/x/sys) for cross-platform colors.
  • CI: added CodeQL scanning workflow using github/codeql-action and actions/checkout.