You need to install it globally. It's just "typescript". https://www.typescriptlang.org/#installation
There's no reason to have it in the repo when you're going to need the rest of the node toolchain and are likely using it with applications or software which leverage node-based tools anyways (webpack, yarn, etc.). In most cases they're going to be vendored in with the project anyways via a yarn lock file, specified in package.json, etc. and part of their grunt or similar build toolchains, not used globally, and want a specific version of TypeScript.
