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/el_GR/Export.json

@@ -0,0 +1,8 @@
+{
+  "fields": {
+    "fieldList": "Λίστα Πεδίων",
+    "exportAllFields": "Εξαγωγή όλων των πεδίων",
+    "format": "Διάταξη",
+    "xlsxTitle": "Τίτλος"
+  }
+}