fix: smooth mobile edit transition and align modal validation behavior (#286)

* fix: reliable Escape key close for all modals via useEscapeKey hook

- Add useEscapeKey hook (document-level keydown listener)
- Retrofit all 12 modal/overlay components to use it
- Remove redundant overlay onKeyDown Escape handlers
- Simplify modal-content onKeyDown to plain stopPropagation
- Replace MedDetailModal's capture-phase useEffect with 3 useEscapeKey calls
- Replace SharedSchedule's inline useEffect with useEscapeKey
- Add mandatory modal rules to UI Consistency skill
- All 777 frontend + 569 backend tests pass

* fix: smooth mobile edit transition and align modal validation behavior

* fix: keep overlay keydown non-closing for Enter key

* fix: show mobile name error when validation already exists

* fix: restore app-level escape priority handling

* fix: prioritize schedule lightbox on Escape

frontend/src/i18n/de.json

@@ -353,6 +353,7 @@
     "intakeReminders": "Einnahme-Erinnerungen aktiviert",
     "automaticTaken": "Automatisch eingenommen",
     "hasNotes": "Hat Notizen",
+    "hasPrescription": "Rezeptverfolgung aktiviert",
     "stockExceedsCapacity": "Bestand überschreitet Packungskapazität — Packungsanzahl anpassen",
     "lightMode": "Zum hellen Modus wechseln",
     "darkMode": "Zum dunklen Modus wechseln"
@@ -452,6 +453,7 @@
     "loose": "lose",
     "none": "Kein",
     "daily": "täglich",
+    "and": "und",
     "everyNDays": "alle {{count}} Tage",
     "day": "Tag",
     "days": "Tage",