`jarvis agents list` crashed with a secondary Rich MarkupError when the
underlying exception message contained markup metacharacters like
`[...]`: the error handler did `console.print(f"[red]Error: {exc}[/red]")`,
and Rich re-parsed the interpolated message as markup (#297).
Escape the dynamic message with rich.markup.escape and keep only the
static "Error:" label styled, so the original error surfaces cleanly
instead of a traceback. Adds a regression test that reproduces the
MarkupError via an exception message with brackets.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
