[scheduler] Timezone Issue 7: Add timezone field to the event model #20598
Description
Current behavior:
- We accept
TemporalSupportedObjectas start/end values - Those objects may not contain timezone info (e.g. 2025-03-05T12:00:00)
- When DST or cross-timezone rendering happens, we cannot know the original timezone
Solution:
- Add an explicit
timezonefield to SchedulerEvent - This gives the engine a reliable data timezone
Benefits:
| Date value | Has TZ info? | Event timezone provided? | Result |
|---|---|---|---|
"2025-03-14T02:00:00Z" |
✔️ | optional | Treated as UTC → converted to the event timezone |
"2025-03-14T02:00:00-05:00" |
✔️ | optional | Treated as UTC-5 → normalized to the event timezone |
"2025-03-14T02:00:00" |
❌ | ✔️ | Interpreted as 02:00 in the event’s timezone |
"2025-03-14T02:00:00" |
❌ | ❌ | Interpret as 02:00 in the adapter’s default timezone |