Move scripts to Nix files

Move the scripts I commonly use into Nix files managed by Home Manager.

Some, like `mounter` and `unmounter` are desktop-only, but this can be
addressed in a future commit to create per-host scripts or
desktop/non-desktop scripts.

This commit also removes a number of unused scripts that are either
included in packages like `git-extras` or aren't used.

modules/home-manager/cli/scripts/default.nix

@@ -1,10 +1,18 @@
-{
-  home = {
-    sessionPath = [ "$HOME/.local/bin" ];
+{ pkgs, ... }:
 
-    file.".local/bin" = {
-      source = ./scripts;
-      recursive = true;
-    };
-  };
+{
+  # TODO: separate desktop-only scripts?
+  home.packages =
+    let
+      scriptNames = [
+        "create-script"
+        "mounter"
+        "move-firefox-screenshots"
+        "setbg"
+        "tag-release"
+        "unmounter"
+        "update-all-git-repos"
+      ];
+    in
+    map (name: pkgs.callPackage ./${name}.nix { }) scriptNames;
 }