Fix event date shown as Jan 1970 in Show Details modals

Event createdAt is a Nostr timestamp in seconds, but
TimeUtils.formatLongToCustomDateTimeWithSeconds expects milliseconds
(Instant.ofEpochMilli), so the date always rendered as Jan 21, 1970.
Convert to milliseconds at the call sites, matching how
ActivitiesScreen and ApplicationsScreen already handle it.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RGJT3Vb91p82TwmDZxqGem

app/src/main/java/com/greenart7c3/nostrsigner/ui/components/EncryptDecryptDetailModal.kt

@@ -97,7 +97,7 @@ fun EncryptDecryptDetailModal(
                         )
                         EventSection(
                             stringResource(R.string.date),
-                            TimeUtils.formatLongToCustomDateTimeWithSeconds(event.createdAt),
+                            TimeUtils.formatLongToCustomDateTimeWithSeconds(event.createdAt * 1000),
                             { copyToClipboard(clipboard, "${event.createdAt}") },
                         )
                         if (event.content.isNotEmpty()) {

app/src/main/java/com/greenart7c3/nostrsigner/ui/components/EventDetailModal.kt

@@ -110,7 +110,7 @@ fun EventDetailModal(
                 )
                 EventSection(
                     stringResource(R.string.date),
-                    TimeUtils.formatLongToCustomDateTimeWithSeconds(event.createdAt),
+                    TimeUtils.formatLongToCustomDateTimeWithSeconds(event.createdAt * 1000),
                     {
                         copyToClipboard(clipboard, "${event.createdAt}")
                     },