feat(diary): enhance predefined activities management and socket event handling

- Added new API endpoints for managing predefined activities, including retrieval, creation, updating, merging, and deduplication.
- Updated socket event handling to improve the mapping of socket events to domain events, ensuring better integration with the diary service.
- Enhanced repository mappers to support detailed mapping of predefined activities and training statistics, including images and member participation data.
- Introduced new UI strings for managing predefined activities, improving user experience in the diary section.

android-app/scripts/check_no_hardcoded_ui_strings.sh

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+ROOT_DIR="$(cd "$SCRIPT_DIR/.." && pwd)"
+
+TARGETS=(
+  "$ROOT_DIR/app/src/main/java/de/trainingstagebuch/app/ui/screens"
+  "$ROOT_DIR/app/src/main/java/de/trainingstagebuch/app/ui/ErrorFeedback.kt"
+  "$ROOT_DIR/app/src/main/java/de/trainingstagebuch/app/viewmodel"
+)
+
+# Guard against introducing hardcoded user-facing UI strings in Compose/viewmodel state handling.
+PATTERN='Text\(\s*"[^"]*[[:alpha:]][^"]*"\s*\)|label\s*=\s*"[^"]*[[:alpha:]][^"]*"|title\s*=\s*"[^"]*[[:alpha:]][^"]*"'
+
+if rg -n --pcre2 "$PATTERN" "${TARGETS[@]}"; then
+  echo ""
+  echo "Hardcoded UI strings gefunden. Bitte auf stringResource()/UiText umstellen."
+  exit 1
+fi
+
+echo "i18n guard ok: keine hardcoded UI strings gefunden."