Install Obelisk

This is a one-time bootstrap guide. It installs the local Obelisk runtime, then uses that runtime to install the official agent skill from github.com/tommy0103/obelisk-skill.

1. Check for the CLI

command -v obelisk >/dev/null 2>&1 && obelisk --version

If this succeeds, skip to step 3. Do not reinstall a working CLI unless the user asked to upgrade or repair it.

2. Install the CLI

Installing a global command changes the user's machine. Show the command and get the user's approval before running one of these official installation methods.