Add exec commands for running arbitrary executables with local bins on PATH

Add exec commands for running arbitrary executables with local bins on PATH: a task in MiMo-V2.6-RL-oss: Agentic RL Environments (MiMo RL release). Add exec commands for running arbitrary executables with local bins on PATH pyarn can already run package scripts, but there's no way to invoke an…

The task

Add exec commands for running arbitrary executables with local bins on PATH pyarn can already run package scripts, but there's no way to invoke an arbitrary executable (for example a binary installed by a dependency) with the project's locally installed tools available on PATH.…

Part of XiaomiMiMo/MiMo-V2.6-RL-oss.