consolidated script documentation into a single md file

wrote documentation on terminal sound effects

added a sound effect for `invoke`

added the function `build-drv`, which is a wrapper for nix-build that
puts the output nix store path to the derivation into an environment
variable instead of symlinking it in the current working directory

overlay/scripts/wm-controls/s_check.nix

@@ -4,6 +4,6 @@ pkgs.writeShellApplication {
   text = ''
     #!/run/current-system/sw/bin/bash
 
-    [ "$SOUNDS_ENABLED" -eq 1 ]
+    [ "$SOUNDS_ENABLED" = "true" ]
   '';
 }