Search v1 (#19)

* Adds description to media items; hooks it up to indexing/media downloading

* Added a search method using postgres fulltext search

* Hooked up search functionality to the search form

* Added persistence to the search form when on search page

lib/pinchflat_web/components/layouts/app.html.heex

@@ -2,7 +2,7 @@
   <.sidebar />
 
   <div class="relative flex flex-1 flex-col overflow-y-auto overflow-x-hidden">
-    <.header />
+    <.header params={@conn.params} />
     <main>
       <div class="mx-auto max-w-screen-2xl p-4 md:p-6 2xl:p-10">
         <.flash_group flash={@flash} />