[tools, cmake] refactor: update/hash check scripts, use tags for some more deps, proper CPMUtil separation (#2666)

Uses tags for a bunch of deps that can use them

Also adds a bunmch of scripts to tools/cpm, notably for checking hashes
and checking for updates.

TODO for the future:
- CI target to check hashes
- Weekly CI to check for updates

Need to get that other CI runner up

additional stuff

- Ports gentoo fixes
- makes solaris work (TODO: sdl2)
- way better docs
- properly separates CPMUtil as a standalone project

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/2666
Reviewed-by: Lizzie <lizzie@eden-emu.dev>
Reviewed-by: MaranBr <maranbr@eden-emu.dev>

tools/cpm/hash.sh

@@ -0,0 +1,25 @@
+#!/bin/sh -e
+
+# SPDX-FileCopyrightText: 2025 crueter
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+# usage: hash.sh repo tag-or-sha
+# env vars: GIT_HOST, USE_TAG (use tag instead of sha), ARTIFACT (download artifact with that name instead of src archive)
+
+REPO="$1"
+[ -z "$GIT_HOST" ] && GIT_HOST=github.com
+GIT_URL="https://$GIT_HOST/$REPO"
+
+if [ "$USE_TAG" = "true" ]; then
+    if [ -z "$ARTIFACT" ] || [ "$ARTIFACT" = "null" ]; then
+        URL="${GIT_URL}/archive/refs/tags/$2.tar.gz"
+    else
+        URL="${GIT_URL}/releases/download/$2/${ARTIFACT}"
+    fi
+else
+    URL="${GIT_URL}/archive/$2.zip"
+fi
+
+SUM=$(wget -q "$URL" -O - | sha512sum)
+
+echo "$SUM" | cut -d " " -f1