Time picker replaced user-friendly scroll-select with unusable +/- spinner — manual time entry no longer possible

Steps to reproduce

1. Create or edit a calendar event
2. Click on the time field
3. Try to enter a specific time manually (e.g. 20:07) or use the mouse scroll wheel for quick selection

Expected behavior

Previous behavior (before 6.3.1): a clean, user-friendly select with 15-minute steps (10:00, 10:15, 10:30, …) navigable with the mouse scroll wheel. Manual entry of
arbitrary times was also possible.

Actual behavior

The time picker is now a native datetime-local input with separate +/- spinners for hours and minutes. No manual text input is accepted — typed values are discarded.
Times are restricted to 5-minute increments. Setting a precise time like 20:07 or 09:33 requires clicking through multiple spinner steps.

Calendar app version

6.4.2

CalDAV-clients used

No response

Browser

Firefox 148.0

Client operating system

No response

Server operating system

No response

Web server

None

Database engine version

None

PHP engine version

None

Nextcloud version

33.0.5

Updated from an older installed version or fresh install

Updated from an older version

List of activated apps

Nextcloud configuration

Web server error log

Log file

Browser log

Additional info

The change was introduced in 6.3.1 via "DatePicker: use native date and time picker" (commit 7ed3e6e). See #8307 for a related report — same root cause, different
perspective: #8307 focuses on the inability to enter arbitrary times, this issue focuses on the overall UX regression. The replacement picker is objectively worse: it
requires more clicks, supports fewer precision options (5m vs 1m), removes scroll-wheel navigation, and does not accept keyboard input. A custom picker that works
correctly would be preferable to the native picker

Start by reviewing commit 7ed3e6e, which introduced the native date and time picker, and compare the related report in #8307. Reproduce the event time-field behavior in Firefox, then verify that users can enter arbitrary times, select 15-minute steps, and navigate selections with the mouse wheel without the current spinner-only restrictions.