Your requirements could not be resolved to an installable set of packages.
Problem 1
- Root composer.json requires pestphp/pest ^4.0.0 -> satisfiable by pestphp/pest[v4.0.0, 4.x-dev].
- pestphp/pest[v4.0.0, ..., 4.x-dev] require pestphp/pest-plugin-mutate ^4.0.0 -> satisfiable by pestphp/pest-plugin-mutate[v4.0.0, 4.x-dev] from composer repo (https://repo.packagist.org) but pestphp/pest-plugin-mutate dev-68766eb0851ca201eefe1ed283708c63abb0a463 is the root package and cannot be modified. See https://getcomposer.org/dep-on-root for details and assistance.