ci: Notarize MacOS Binaries and Add Flat Package Installers (#3571)

* ci: Notarize MacOS

* Modify logging and documentation to be better

* Make a copy of certain parts of the deploy workflow

* Delete testing workflow

install/macos_packages/build_distribution_package.sh

@@ -0,0 +1,67 @@
+#!/bin/bash
+
+component_package="$1"
+resources="$2"
+arch="$3"
+
+usage(){
+    echo "Builds a distribution package for macOS."
+    echo "Assumes that the following items already exist:"
+    echo "    - A starship component package"
+    echo "    - Resources in a pkg_resources directory"
+    echo "Usage: $0 <path-to-component-package> <path-to-pkg-resources> <arch>"
+    echo "    where arch is one of \"arm64\" or \"x86_64\""
+}
+
+script_dir="$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )"
+source "$script_dir/common.sh"
+
+if [[ "$OSTYPE" != 'darwin'* ]]; then
+    error "This script only works on MacOS"
+fi
+
+if [[ "${3-undefined}" = "undefined" ]]; then
+    usage
+    exit 1
+fi
+
+# Generate a distribution file with the appropriate architecture plists
+if [[ "$arch" == "x86_64" || "$arch" == "x64" ]]; then
+  archplist="$script_dir/x86_64.plist"
+elif [[ "$arch" == "arm64" || "$arch" == "aarch64" ]]; then
+  archplist="$script_dir/aarch64.plist"
+else
+  error "Invalid architecture: $arch"
+fi
+
+productbuild --synthesize --package starship-component.pkg --product "$archplist" starship_raw.dist
+
+# A terrible hacky way to insert nodes into XML without needing a full XML parser:
+# search for a line that matches our opening tag and insert our desired lines after it
+# Solution taken from https://www.theunixschool.com/2012/06/insert-line-before-or-after-pattern.html
+
+while read -r line
+do
+  echo "$line"
+  if echo "$line" | grep -qF '<installer-gui-script '; then
+    echo '<welcome file="welcome.html" mime-type="text-html" />'
+    echo '<license file="license.html" mime-type="text-html" />'
+    echo '<conclusion file="conclusion.html" mime-type="text-html" />'
+    echo '<background file="icon.png" scaling="proportional" alignment="bottomleft"/>'
+  fi
+done < starship_raw.dist > starship.dist
+
+# The above script does not correctly take care of the last line. Apply fixup.
+echo '</installer-gui-script>' >> starship.dist
+
+echo "Creating distribution package with following distribution file:"
+cat starship.dist
+
+echo "Resource directory is $resources"
+echo "Component package is $component_package"
+
+# Build the distribution package
+productbuild --distribution starship.dist --resources "$resources" --package-path "$component_package" starship-unsigned.pkg
+
+# Clean up the distribution files
+rm -- *.dist