swarm ui: one review page

The two review tabs, runs and try-out, are one: /review. It is a column of
three sections: try a classification and the classifier settings, each a
folded bar (the settings' bar says what they are now), then the recent runs,
always open. The settings had been pinned under the try-out form; they are now
a section of their own. A new Disclosure primitive is the folding bar, a
native details wearing the Panel's classes, so the folded and open sections
read as the same surface.

/review-runs and /review-tryout are gone, with no redirect.

frontend/packages/swarm-ui/src/ui/disclosure/Disclosure.tsx

@@ -0,0 +1,50 @@
+// <Disclosure> — a Panel that folds: the header row is the control, and the
+// body shows only while it is open. For a section a page keeps within reach
+// but that is not the point of the page, such as a form used now and then.
+// It is a native `<details>`, so the keyboard and assistive tech get the
+// open/closed state for free, and it wears the Panel's own classes, so a
+// Disclosure and a Panel on one page read as the same kind of surface.
+//
+// Controlled: `open` and `onToggle`, so a page can open it for the user (a
+// run started, say). The body stays in the DOM while it is shut, so what was
+// typed into it survives a fold. `hint` is a short line beside the title that
+// says what is in there without opening it.
+import type { ComponentChildren } from "preact";
+import "../panel/Panel.css";
+import "./Disclosure.css";
+
+export function Disclosure({
+  title,
+  icon,
+  hint,
+  open,
+  onToggle,
+  children,
+}: {
+  title: string;
+  icon?: string;
+  hint?: ComponentChildren;
+  open: boolean;
+  onToggle: (open: boolean) => void;
+  children: ComponentChildren;
+}) {
+  return (
+    <details
+      class="ui-panel ui-disclosure"
+      open={open}
+      onToggle={(e) => onToggle((e.currentTarget as HTMLDetailsElement).open)}
+    >
+      <summary class="ui-panel-header ui-disclosure-summary">
+        {icon ? (
+          <span class="ui-panel-icon" aria-hidden="true">
+            {icon}
+          </span>
+        ) : null}
+        <h2 class="ui-panel-title">{title}</h2>
+        {hint ? <span class="ui-disclosure-hint">{hint}</span> : null}
+        <span class="ui-disclosure-chevron" aria-hidden="true" />
+      </summary>
+      <div class="ui-panel-body">{children}</div>
+    </details>
+  );
+}