## Summary
- When CSV dates are ambiguous (e.g. `05/03/2024` parses as both
DD-MM-YYYY and MM-DD-YYYY), the auto-detection heuristic now uses the
user's locale preference as a tie-breaker instead of relying on array
order
- Adds `getLocaleDateFormat()` helper that maps locale strings to their
expected date format (US → MM-DD-YYYY, most others → DD-MM-YYYY, CJK →
YYYY-MM-DD)
- Passes locale from Inertia shared props to both transaction and
balance import flows
Closes#100
## Test plan
- [x] Added 15 Vitest tests for `getLocaleDateFormat` and
`autoDetectDateFormat` with locale tie-breaking
- [ ] Manual test: Import CSV with ambiguous dates (day ≤ 12) using a
non-US locale, verify DD-MM-YYYY is preferred
- [ ] Manual test: Import CSV with unambiguous dates (day > 12), verify
locale does NOT override correct detection
a19a8d52ec