Add time selection to the outage start date filter

[annpandev]

Summary

• Adds a time-of-day picker to DateSelector, alongside the existing calendar day picker, so users can filter outages by a precise start date and time instead of only a day.
• Selecting a day from the calendar keeps whatever time was already set (defaults to midnight for a new value); a separate time input lets you adjust just the time-of-day.
• Also adds a "type exact date & time" datetime-local input as a manual entry option, with the local timezone label shown next to the time field.
• Display text now shows date + time (e.g. "Sep 15, 2026, 02:14 PM") instead of just the date.

Test plan

• Manually verified picking a day keeps the previously-set time
• Manually verified adjusting the time field updates the value without changing the day
• Manually verified typing into the datetime-local input updates the filter
• Verified min/max date bounds still apply correctly

[amandahmeng]

New interaction - when the user clicks the outage start have the calendar immediately open (skip the after/before window)