v1.5.3

Added

• Redesigned About dialog. The Help -> About entry now opens a proper
  two-column dialog (logo, version, description, credits and project links)
  instead of a plain message box. Contributors are credited there.

Changed

• Leaner translation files. Shared button and label wording (Cancel, Save,
  Close, ...) is now stored once under common.* keys instead of being
  duplicated, and a hygiene guard keeps the catalogues free of duplicate
  values and in sync across languages. No visible text changed.