Fix mobile UI: slide panel padding and datetime picker clicks

- Increase event detail panel bottom padding from pb-20 to pb-28 to
  prevent delete button from being obscured by mobile nav + safe area
- Change datetime picker from hx_on_click/hx_on_change to standard
  onclick/onchange attributes (HTMX doesn't recognize hx-on-* syntax)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/animaltrack/web/templates/actions.py

@@ -158,7 +158,7 @@ def event_datetime_field(
                     toggle_text,
                     cls="text-blue-400 hover:text-blue-300 cursor-pointer underline",
                     data_datetime_toggle=field_id,
-                    hx_on_click=f"toggleDatetimePicker('{field_id}')",
+                    onclick=f"toggleDatetimePicker('{field_id}')",
                 ),
                 cls="text-sm",
             ),
@@ -169,7 +169,7 @@ def event_datetime_field(
                     value=initial_value,
                     cls="uk-input w-full mt-2",
                     data_datetime_input=field_id,
-                    hx_on_change=f"updateDatetimeTs('{field_id}')",
+                    onchange=f"updateDatetimeTs('{field_id}')",
                 ),
                 P(
                     "Select date/time for this event (leave empty for current time)",

src/animaltrack/web/templates/event_detail.py

@@ -77,7 +77,7 @@ def event_detail_panel(
         # Delete button (admin only, not for tombstoned events)
         delete_section(event.id) if user_role == UserRole.ADMIN and not is_tombstoned else None,
         id="event-panel-content",
-        cls="bg-[#141413] h-full overflow-y-auto pb-20 md:pb-0",
+        cls="bg-[#141413] h-full overflow-y-auto pb-28 md:pb-0",
     )