Dashboard: keep list/chart alive when the digest detail fetch fails

A transient failure (e.g. container swap during redeploy) used to leave the
body panel silently empty; show a retry hint in the body instead.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

dashboard/src/client/main.ts

@@ -348,7 +348,17 @@ async function main(): Promise<void> {
   const select = async (week: string) => {
     selected = week;
     renderList(summaries, selected, (w) => void select(w));
-    await showDigest(week);
+    try {
+      await showDigest(week);
+    } catch (err) {
+      // 서버 재기동 순간 등 일시 실패: 본문만 안내로 대체하고 목록/차트는 살려둔다
+      console.error(err);
+      const body = byId<HTMLElement>("digest-body");
+      body.textContent = "";
+      body.append(
+        el("p", "chart-empty", `${week} 다이제스트를 불러오지 못했습니다 — 새로고침하거나 다시 선택해 주세요.`),
+      );
+    }
   };
   await select(selected);
 }