add starship install script

.config/yadm/bootstrap.d/install-starship

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+set -eu
+
+VERSION="1.9.1"
+INSTALL_DIR="${HOME}/.local/bin"
+INSTALLED_VERSION=""
+
+if [[ -x "$(command -v starship)" ]]; then
+  INSTALLED_VERSION="$(starship -V | grep starship | grep -o '[0-9.]\+')"
+fi
+
+if [[ "$VERSION" == "$INSTALLED_VERSION" ]]; then
+  echo "Starship version ${VERSION} already installed."
+  exit 0
+fi
+
+echo "Installing starship version ${VERSION}..."
+
+URL="https://github.com/starship/starship/releases/download/v${VERSION}/starship-x86_64-unknown-linux-gnu.tar.gz"
+
+echo "Downloading from ${URL}..."
+TARGET="$(download "$URL")"
+
+if [[ -d "${INSTALL_DIR}" ]] ; then
+  echo "Removing old starship command..."
+  rm -f "${INSTALL_DIR}/starship"
+fi
+
+echo "Unpacking starship command to ${INSTALL_DIR}..."
+mkdir -p "${INSTALL_DIR}"
+tar --directory="${INSTALL_DIR}" -xf "${TARGET}" starship
+chmod +x "${INSTALL_DIR}/starship"