fix: prevent UI freeze after saving signed log entries

Cache plaintext list metadata on entry save so the journal list avoids
full decrypt per row, and batch sync pull writes with main-thread yields.

Co-authored-by: Cursor <cursoragent@cursor.com>

client/src/utils/entryListCache.ts

@@ -0,0 +1,64 @@
+import { db, type EntryListCache, type LocalEntry } from '../services/db.js'
+import { getSkipperSignStatus, type SkipperSignStatus } from './signatures.js'
+
+export type { EntryListCache }
+
+export interface EntryListItem {
+  id: string
+  date: string
+  dayOfTravel: string
+  departure: string
+  destination: string
+  updatedAt: string
+  skipperSignStatus: SkipperSignStatus
+}
+
+export async function buildEntryListCache(decrypted: Record<string, unknown>): Promise<EntryListCache> {
+  return {
+    date: String(decrypted.date || ''),
+    dayOfTravel: String(decrypted.dayOfTravel || ''),
+    departure: String(decrypted.departure || ''),
+    destination: String(decrypted.destination || ''),
+    skipperSignStatus: await getSkipperSignStatus(decrypted)
+  }
+}
+
+export function entryListItemFromLocal(entry: LocalEntry): EntryListItem | null {
+  if (!entry.listCache) return null
+  return {
+    id: entry.payloadId,
+    date: entry.listCache.date,
+    dayOfTravel: entry.listCache.dayOfTravel,
+    departure: entry.listCache.departure,
+    destination: entry.listCache.destination,
+    updatedAt: entry.updatedAt,
+    skipperSignStatus: entry.listCache.skipperSignStatus
+  }
+}
+
+export type LocalEntryPut = Omit<LocalEntry, 'listCache'> & { listCache?: EntryListCache }
+
+/** Persist entry ciphertext and optional plaintext list cache for fast journal list loads. */
+export async function putEntryRecord(
+  record: LocalEntryPut,
+  decryptedForCache?: Record<string, unknown>
+): Promise<void> {
+  const listCache =
+    record.listCache ??
+    (decryptedForCache ? await buildEntryListCache(decryptedForCache) : undefined)
+
+  await db.entries.put({
+    ...record,
+    ...(listCache ? { listCache } : {})
+  })
+}
+
+/** Backfill list cache after a legacy decrypt — fire-and-forget is fine. */
+export function persistEntryListCache(
+  payloadId: string,
+  decrypted: Record<string, unknown>
+): void {
+  void buildEntryListCache(decrypted)
+    .then((listCache) => db.entries.update(payloadId, { listCache }))
+    .catch((err) => console.warn('Failed to persist entry list cache:', err))
+}