xdg: update npm prefix

and cleanup some stale values

* `update-notifier` was dropped in v7: npm/cli@d062b2c
* `devdir` no longer defaults to ~/.node-gyp: nodejs/node-gyp@8a83972
* Some tools try to respect npm's cache dir but only read `npm_config_cache`

.config/fish/conf.d/__xdg.fish

@@ -44,14 +44,9 @@ set -gx LESSHISTFILE /dev/null
 
 # node
 set -gx NODE_REPL_HISTORY /dev/null
-set -gx NO_UPDATE_NOTIFIER 1 # used by npm: https://github.com/yeoman/update-notifier/issues/180
-set -gx NPM_CONFIG_CACHE $XDG_CACHE_HOME/npm
-set -gx NPM_CONFIG_DEVDIR $XDG_DATA_HOME/node-gyp
-set -gx NPM_CONFIG_INIT_MODULE $XDG_CONFIG_HOME/npm/config/npm-init.js
-set -gx NPM_CONFIG_PREFIX $XDG_DATA_HOME/npm
-set -gx NPM_CONFIG_USERCONFIG $XDG_CONFIG_HOME/npm/npmrc
-set -p XDG_BIN_DIRS $NPM_CONFIG_PREFIX/bin
-__maybe_mkdir $NPM_CONFIG_PREFIX/lib
+set -gx npm_config_cache $XDG_CACHE_HOME/npm
+set -gx npm_config_prefix ~/.local
+set -gx npm_config_userconfig $XDG_CONFIG_HOME/npm/npmrc
 
 # pip
 set -gx PIP_CACHE_DIR $XDG_CACHE_HOME/pip