Responsive UI improvements (#41)

* Improved responsive UX for media profiles

* Improved responsiveness for other pages

* Added docs; fixed up stragglers

lib/pinchflat_web/components/layouts/partials/header.html.heex

@@ -3,7 +3,7 @@
     <div class="flex items-center gap-2 sm:gap-4 lg:hidden">
       <button
         class="z-99999 block rounded-sm border border-stroke bg-white p-1.5 shadow-sm dark:border-strokedark dark:bg-boxdark lg:hidden"
-        @click.stop="sidebarToggle = !sidebarToggle"
+        @click.stop="sidebarVisible = !sidebarVisible"
       >
         <.icon name="hero-bars-3" />
       </button>