Adds Italian as an interface language: 1,227 rows written from the
English strings with Italian desktop-CAD vocabulary (Disegna,
Tratteggio, Quota, Direttrice, layer, spazio modello/carta). Two
`menu` entries keep the menu-bar headings apart from the command and
tool-group labels: View → Visualizza (object label: Vista) and
Modify → Edita (tool group: Modifica). Italian integer plurals follow
the English rule (one, other).
Registered in i18n::LANGUAGES and Preference (code `it`), reported in
the catalog tests, with a locale/preference/plural/menu/font test;
attributed in ATTRIBUTION.md; README, ROADMAP, docs/localization.md,
docs/localization-parity.md, docs/control-protocol.md and the Options
doc comment list the language.
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>
Rebase onto main: the interface language is saved with main's other
preferences (cadcraft.prefs, beside the theme) instead of its own storage
key, on desktop and web; strings main added or changed in the touched
places (Dynamic Input settings, Properties header and current-property
rows, block picker, theme and command-history menu items, open/save
filters) are wrapped and translated; main's native-menu poll order is kept.
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
