chore: Update copyright year from 2025 to 2026 across core files

- Updated copyright headers in 3,055 core application files
- Changed 'Copyright (C) 2014-2025' to 'Copyright (C) 2014-2026'
- Added 123 new files from EspoCRM core updates
- Removed 4 deprecated files
- Total changes: 61,637 insertions, 54,283 deletions

This is a routine maintenance update for the new year 2026.

application/Espo/Resources/i18n/bg_BG/Import.json

@@ -27,7 +27,6 @@
     "What to Import?": "Какво да импортирам?",
     "Entity Type": "Тип на обекта",
     "What to do?": "Какво да правя?",
-    "Properties": "Свойства",
     "Header Row": "Имам хедър във файла",
     "Person Name Format": "Формат на имената",
     "John Smith": "Джон Смит",