[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/which.sh

@@ -0,0 +1,15 @@
+#!/bin/sh -e
+
+# SPDX-FileCopyrightText: 2025 crueter
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+# check which file a package is in
+# shellcheck disable=SC1091
+. tools/cpm/common.sh
+
+# shellcheck disable=SC2086
+JSON=$(find $DIRS -maxdepth "$MAXDEPTH" -name cpmfile.json -exec grep -l "$1" {} \;)
+
+[ -z "$JSON" ] && echo "!! No cpmfile definition for $1"
+
+echo "$JSON"