Switch from an Action to gh release

Fewer supply chain risks whooooo

.github/scripts/draft-release.sh

@@ -0,0 +1,25 @@
+#!/bin/bash
+set -euo pipefail
+
+tag=$1
+[ $# -eq 1 ]
+
+flags=(--draft --fail-on-no-commits --verify-tag)
+if [[ "$tag" = v*-rc* ]]; then
+	flags+=(--prerelease)
+fi
+
+files=(
+	win64/rgbds-win64.zip
+	win32/rgbds-win32.zip
+	macos/rgbds-macos.zip
+	linux/rgbds-linux-x86_64.tar.xz
+	rgbds-source.tar.gz
+)
+
+set -x
+gh release create "${flags[@]}" --notes-file - "$tag" "${files[@]}" <<"EOF"
+Please ensure that the packages below work properly.
+Once that's done, replace this text with the changelog, un-draft the release, and update the `release` branch.
+By the way, if you forgot to update `include/version.hpp`, RGBASM's version test is going to fail in the tag's regression testing! (Use `git push --delete origin <tag>` to delete it)
+EOF