Translations

Texts are written in Italian in the code and wrapped in _() (backingtrack/i18n.py); the English translations are in backingtrack/locale_en.py (EN for texts, GROOVES_EN for groove descriptions). Module-level constants (the F1 guide, scale descriptions…) stay raw and are translated where they are shown. A test fails if a text has no translation or if its %s placeholders differ. The documentation lives in docs/it/ and docs/en/; python3 docs/make_docs.py regenerates the groove and song tables from the data and the navigation bar of every page.