Interactive Dialog: Date picker displays previous day when device is in positive UTC offset timezones (e.g. UTC+5)

[Sanchezz17]

When selecting a date using the date picker element in an Interactive Dialog, the field visually displays the previous day's date prior to submitting the form. However, once the form is submitted, the payload sent to the server contains the correct date.This behavior depends entirely on the device's local timezone. The bug is highly reproducible in timezones with positive UTC offsets (e.g., Yekaterinburg Time / YEKT / UTC+5) but disappears when switching the device timezone to UTC±0 or negative UTC offsets.

Environment

• Mattermost Mobile App Version: Latest (2.43.0)
• OS: iOS / Android (Applies to both)
• Device Timezone: Positive UTC offset (e.g., UTC+5 / Yekaterinburg Time)

Steps to Reproduce

1. Set your mobile device timezone to a positive offset from UTC (e.g., UTC+5 / Yekaterinburg / Asia/Yekaterinburg).
2. Open an Interactive Dialog containing a date or datetime picker element type.
3. Click the field to open the date picker and select any date (for example, August 24).
4. Save the selection and look at the dialog form before clicking submit.

Expected Behavior
The dialog field should display the exact date selected by the user (August 24).

Observed Behavior
The dialog field visually shows the day before the selected date (August 23).
Note: If the form is submitted, the backend integration actually receives the correct date payload, indicating this is purely a frontend timezone offset/rendering bug.

Additional Context
If you change the device's timezone to UTC+0 or any negative offset (e.g., UTC-5), the date displays correctly.