hub-ui-onboard: the install never settles when the package manager hangs #464

If the package manager hangs after you click Install, the onboarding waits forever. runInstall in packages/hub-ui-onboard/src/install.ts has no timeout on exec, so there's never an error or a hint to run the command yourself.

I hit this with Nuxt 5 nightly and @nuxt/devtools-onboard. On pnpm 10, pnpm add @nuxt/devtools@^4.0.0-beta.7 hangs forever because of a pnpm resolver bug, which pnpm 11 fixes. I ran that command by hand, not through the panel.

The hang itself is pnpm's bug. From the panel, though, any stuck install looks the same. Would you take a PR that stops the install after a while, or reports that it's still running, and shows the command to run in a terminal?