Three related fixes from manual smoke testing:
- Zod schema: drop min(1) on note field across all four schemas — note is
optional in real usage, and the modal initialized it to empty.
- assertNotPastDate: replace toISOString() (UTC) with local-time getters
to match the rest of the codebase. Fixes off-by-one near day boundaries.
- createEntry / updateEntry: also check the date_to endpoint for past
dates, so a range can't extend backwards into the past even when its
start is today or future. Defense in depth.
Modal: drop `required` attribute and asterisk from the note field. Tests:
add 5 new cases covering empty note, past date HTTP rejection, and the
new to-endpoint check in updateEntry.
