The fitness UI translation table previously lived as one combined
object in fitnessI18n.ts where every entry held both languages. That
hides drift (an English string can silently disappear without TypeScript
noticing) and makes adding strings a multi-edit dance.
Split into src/lib/i18n/fitness/{de,en}.ts. de.ts is the source of
truth for the key set; en.ts uses `as const satisfies
Record<keyof typeof de, string>` so any missing English translation is
a build-time error. fitnessI18n.ts now re-exports both as a typed
table m and adds FitnessLang/FitnessKey types — the existing
t/fitnessSlugs/fitnessLabels API stays so call sites don't churn.
The strict typing immediately surfaced one real bug: t('initializing_gps')
was being called from the active workout page but the key never existed
in the dictionary, so it had been rendering the literal string
'initializing_gps' through the fallback. Added the missing key in both
locales.
Tightened BodyPartCard.labelKey and the body-parts Step JSDoc to
FitnessKey instead of plain string so card data drift catches drift at
the data site, not the call site. Two dynamic-key sites (partKeyMap
fallbacks for unmapped measurement keys) are cast pragmatically.
The 360-entry split was done by a one-shot extraction script
(scripts/split-fitness-i18n.ts) — kept for re-use against
cospendI18n.ts and calendarI18n.ts in follow-up commits.
Alexander
609405da81
