feat(app): More info about a card

"More info", in a card's menu while studying or in the list, shows when
it was made and last changed (its ids say), its id and its studyset's
(and its PDF's), each copied with a tap, and how often it was studied
and when last. The sheet is a shared one, for notes and paths to follow.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

halkyon_learn_flutter/lib/l10n/app_de.arb

@@ -628,6 +628,17 @@
   "commonSave": "Speichern",
   "commonClose": "Schließen",
   "commonUndo": "Rückgängig",
+  "moreInfo": "Weitere Informationen",
+  "moreInfoCreated": "Erstellt",
+  "moreInfoModified": "Zuletzt geändert",
+  "moreInfoItemId": "Element-ID",
+  "moreInfoStudysetId": "Lernset-ID",
+  "moreInfoPdfId": "PDF-Quellen-ID",
+  "moreInfoReviews": "Wiederholungen",
+  "moreInfoReviewCount": "Anzahl Wiederholungen",
+  "moreInfoLastReviewed": "Zuletzt wiederholt",
+  "moreInfoCopy": "Kopieren",
+  "copiedToClipboard": "In die Zwischenablage kopiert",
   "commonTryAgain": "Erneut versuchen",
   "personDataFailed": "Die Daten dieses Geräts konnten nicht geöffnet werden.",
   "sessionUnreachable": "Der Server war nicht erreichbar.",