give the rollup glyph back its spin animation

The extraction dropped the old banner's `spinner` class on the glyph
span (`el('span', { class: 'glyph spinner' }, ...)`) - JobqRollup.tsx
rendered a static `.jqr-glyph` with no animation rule anywhere.
`.spinner` (shared/base.css) is already imported by both consumers, so
just reuse it on the glyph rather than duplicating the keyframes.

argus caught this on review - a single-frame screenshot can't tell a
frozen spinner from a missing one, which is exactly why it slipped
past the PR's visual verification.

frontend/packages/shared/src/jobq-rollup/JobqRollup.tsx

@@ -18,6 +18,11 @@
 // /builds.html; swarm-ui's /jobs page omits it — a link to the page
 // you're already on is noise).
 //
+// The glyph carries `.spinner` (`@hive/shared/base.css`, already
+// imported by both consumers) for the "actively happening" spin —
+// not redeclared in jobq-rollup.css, since a static screenshot can't
+// tell a frozen spinner from a missing one; caught by argus's review.
+//
 // Two ways to use this, same shape as JobqGraph: JSX (swarm-ui) —
 // `<JobqRollup endpoint="..." queueHref="..." />`. Or imperative mount
 // (dashboard/src/swarm.js, plain `.js`) — `mountJobqRollup(container,
@@ -76,7 +81,7 @@ export function JobqRollup({ endpoint, queueHref, refreshToken = 0 }: JobqRollup
 
   return (
     <div class="jqr-summary">
-      <span class="jqr-glyph">◐</span>{' '}
+      <span class="jqr-glyph spinner">◐</span>{' '}
       <strong>build queue</strong> — {parts.join(' · ')}{' '}
       {queueHref && (
         <a class="jqr-link" href={queueHref}>view queue →</a>