v3: lots of small UI tweaks and fixes

src/components/PageShell.tsx

@@ -1,6 +1,5 @@
 import { type ReactNode } from "react";
 import { AppHeader } from "./AppHeader.tsx";
-import { SearchBar } from "./SearchBar.tsx";
 
 interface PageShellProps {
   children: ReactNode;
@@ -14,7 +13,7 @@ export function PageShell(
 ) {
   return (
     <div className="page-shell">
-      <AppHeader centerSlot={centerSlot ?? <SearchBar />} />
+      <AppHeader centerSlot={centerSlot} />
       <main
         className={`page-content${centered ? " page-content--centered" : ""}`}
       >