perf(release-cleanup): selectReleasesToDelete 預先計算時間戳

排序前先一次性計算各 release 的 created_at 時間戳,避免在排序比較器中
重複呼叫 Date.parse;排序結果與原行為等價。

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/releases.js

@@ -17,8 +17,12 @@ export function selectReleasesToDelete(releases, keepCount) {
     const time = Date.parse(release?.created_at)
     return Number.isNaN(time) ? 0 : time
   }
-  const sorted = [...releases].sort((a, b) => createdTime(b) - createdTime(a))
-  return sorted.slice(keepCount)
+  // 先一次性計算每筆的時間戳,避免在排序比較中重複呼叫 Date.parse。
+  return releases
+    .map((release) => ({ release, time: createdTime(release) }))
+    .sort((a, b) => b.time - a.time)
+    .map((entry) => entry.release)
+    .slice(keepCount)
 }
 
 /**