Restructure modules/shared and update all imports

- Delete 2024-12-rework/ folder
- Rename modules/hosts/common to modules/shared, then split into:
  - modules/shared/home/general
  - modules/shared/home/linux
  - modules/shared/nixos
- Update all import paths throughout the codebase
- Update lib/*.nix to use new paths
- Fix hardcoded /Users/${username} to use config.home.homeDirectory
- Update README and examples/flake-structure.nix

modules/shared/nixos/ripping.nix

@@ -0,0 +1,23 @@
+{ pkgs, ... }: {
+  # Be sure this is added if on NixOS
+  # boot.kernelModules = [ "sg" ];
+
+  # Also, get KEYDB.cfg per https://wiki.archlinux.org/title/Blu-ray
+
+  environment.systemPackages = with pkgs; [
+    abcde
+    asunder
+    handbrake
+    lame
+    libaacs
+    libbdplus
+    libbluray
+    libdvdcss
+    libdvdnav
+    libdvdread
+    makemkv
+    mkvtoolnix
+    mkvtoolnix-cli
+  ];
+}
+