fix(datetime): use Vietnam timezone for dates and display
Summary
Standardize frontend date input, conversion, filtering, and display using Asia/Ho_Chi_Minh.
Key Changes
- Added centralized frontend business-time utilities.
- Displayed absolute timestamps explicitly in the Vietnam timezone.
- Sent Transaction, Budget, and Saving Goal dates as
YYYY-MM-DD. - Removed device-timezone-dependent date parsing.
- Removed the artificial noon workaround from Transaction forms.
- Interpreted transfer and contribution
datetime-localvalues as Vietnam wall-clock time. - Converted datetime inputs to offset-aware UTC ISO timestamps before API submission.
- Built report date boundaries using
Asia/Ho_Chi_Minh. - Removed
timezoneOffsetMinutesfrom report requests. - Updated Transaction filters, Budget filters, Saving Goal filters, clocks, and date displays.
API Contract Changes
- Transaction
date:YYYY-MM-DD - Budget
startDate/endDate:YYYY-MM-DD - Saving Goal
targetDate:YYYY-MM-DD - Report responses use
timeZone: "Asia/Ho_Chi_Minh" - Report requests no longer send the device timezone offset.