fix(design): the table header takes the B9 fade utility, and every size is dvh, not vh (E28 S3d4)

The table header carried an arbitrary-value copy of fade-below; a contract refuses a hand gradient of a surface colour. 100vh is the viewport with a tablet browser's toolbar retracted, so h-screen / min-h-screen / static vh hid the last rows under it; a contract holds dvh (the Plex player stage changes with S3f, where it is played on the tablet).

frontend/src/components/IssueComposer.tsx

@@ -756,7 +756,7 @@ function ReviewList({
           {t("recorder.composer.reviewDone")}
         </Button>
       </div>
-      <ul className="max-h-[60vh] overflow-y-auto rounded-xl border border-border bg-bg/60 font-mono text-xs">
+      <ul className="max-h-[60dvh] overflow-y-auto rounded-xl border border-border bg-bg/60 font-mono text-xs">
         {rows.map((row) => {
           const tag = LEVEL_TAG[row.level];
           const off = excluded.has(row.id);
@@ -813,7 +813,7 @@ function IssuePreview({
     return (
       <div className="flex flex-col gap-1.5">
         <p className="text-xs text-muted">{t("recorder.composer.previewLocal")}</p>
-        <pre className="max-h-[60vh] overflow-auto whitespace-pre-wrap rounded-xl border border-border bg-bg/60 p-3 font-mono text-xs">
+        <pre className="max-h-[60dvh] overflow-auto whitespace-pre-wrap rounded-xl border border-border bg-bg/60 p-3 font-mono text-xs">
           {text}
         </pre>
       </div>