feat: Add global loading indicator to top nav

[gustavoguichard]

According to @brophdawg11 's suggestion and issue #163 , I added this POC to the root.tsx.

In the example below I added a await sleep(2000) to the blog loaders and the theme switch action to see the complete animation and the places where the progressbar stops in both slow actions and loaders.

This was taken from my blog post and I've been using this code successfully in almost all my Remix apps.
I appreciate any feedback if rejected and willing to make any modifications requested. ;)

I've chosen a gradient from bg-blue-brand to bg-aqua-brand I think works good on both dark and light modes.

Preview:

[gustavoguichard]

I noticed the GIF preview got a lil cut off the top. The actual bar is slightly taller (h-1 = 4px):

[brookslybrand]

Thanks @gustavoguichard for taking this on! Mostly little suggestions/code nits

[brookslybrand]

Small nit: can we import the hooks from React. It's not a big thing, just trying to get more uniform into this codebase to that pattern

Suggested change

	import * as React from "react";
	import { useRef, useState, useEffect } from "react";

[brookslybrand]

@brophdawg11 since you added the suggestion I wanted to bring this to your attention in case you wanted to provide feedback

[gustavoguichard]

@brookslybrand , applied the suggestions ;)