⚠️ Rework completely how transitions works

- Use Svelte/Sapper native if and transitions to show either the page content or the loader, then load each page animationIn
- Code is safe on SSR side, using process.browser on this if
- The <main> element is on position absolute to fade nicely the different pages
- Code cleaning

src/atoms/LinkTranslate.svelte

@@ -3,10 +3,9 @@
     export let text = ''
     export let target = null
     export let rel = null
-    export let noScroll = null
 </script>
 
-<a class="link-translate" {href} {target} {rel} sapper-noscroll={noScroll}>
+<a class="link-translate" {href} {target} {rel}>
     <slot />
     <div class="text" data-text={text}>
         <span>{text}</span>