perf(javascript): replace add-node-modules-path

The add-node-modules-path package calls `npm bin` to locate the
node_modules/.bin, and does so while invoking the user's $SHELL, which
can be very expensive depending on the user's shell configuration,
possibly adding seconds to the startup time of any JS/TS file.

To mitigate this, I replace the package with a much faster, and in-house
heuristic. Folks with more complex needs should be using direnv anyway.

Fix: #6878

modules/lang/javascript/config.el

@@ -323,7 +323,7 @@ to tide."
            typescript-mode
            solidity-mode)
   :when (locate-dominating-file default-directory "package.json")
-  :add-hooks '(add-node-modules-path npm-mode))
+  :add-hooks '(+javascript-add-npm-path-h npm-mode))
 
 (def-project-mode! +javascript-gulp-mode
   :when (locate-dominating-file default-directory "gulpfile.js"))