Simplify notification badges, improve performance (#57)

Co-authored-by: Jon Staab <shtaab@gmail.com>

src/routes/chat/[chat]/+page.svelte

@@ -4,18 +4,10 @@
   import {append, uniq} from "@welshman/lib"
   import {pubkey} from "@welshman/app"
   import Chat from "@app/components/Chat.svelte"
-  import {notifications, setChecked} from "@app/util/notifications"
   import {splitChatId} from "@app/core/state"
 
   const {chat} = $page.params as MakeNonOptional<typeof $page.params>
   const pubkeys = uniq(append($pubkey!, splitChatId(chat)))
-
-  // We have to watch this one, since on mobile the badge will be visible when active
-  $effect(() => {
-    if ($notifications.has($page.url.pathname)) {
-      setChecked($page.url.pathname)
-    }
-  })
 </script>
 
 <Chat {pubkeys} />