#1192 start date bug

[jasonk55]

Changes

Fix start date off-by-one bug by normalizing client-provided dates to the user’s local midnight converted to UTC before persisting.

Notes

This change is timezone agnostic, so if someone in another timezone chooses a day (e.g. 9/24/25) for the start date, this is the date for everyone else.

To Do

Any remaining things that need to get done

• Make the frontend render the date correctly according to user's timezone

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Closes #1192

[gcooper407]

thanks for making those fixes, looks good!

[walker-sean]

Can we make this standard for how we handle dates in the frontend and backend to avoid this issue in other places