Add date-aware time slot picker for rescheduling

Enhanced TimeSlotPickerModal with:
- Date selection via date input and navigation arrows
- Passed time slots filtered out (only show future slots for today)
- Complete schedule picker (date + time in one modal)
- Dynamic slot availability based on selected date
- Better UX with date/time sections clearly separated

Updated AdminConsulting to:
- Use editSessionDate when opening time slot picker
- Pass selected date back from modal to parent
- Handle date changes during rescheduling

Fixes the issue where admins could only select time slots for the original
session date, not the new rescheduled date.

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

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

src/pages/admin/AdminConsulting.tsx

@@ -132,11 +132,12 @@ export default function AdminConsulting() {
     setDialogOpen(true);
   };
 
-  const handleTimeSlotSelect = (startTime: string, endTime: string, totalBlocks: number, totalDuration: number) => {
+  const handleTimeSlotSelect = (startTime: string, endTime: string, totalBlocks: number, totalDuration: number, selectedDate: string) => {
     setEditStartTime(startTime);
     setEditEndTime(endTime);
     setEditTotalBlocks(totalBlocks);
     setEditTotalDuration(totalDuration);
+    setEditSessionDate(selectedDate);
     setTimeSlotPickerOpen(false);
   };
 
@@ -1089,7 +1090,7 @@ export default function AdminConsulting() {
           <TimeSlotPickerModal
             open={timeSlotPickerOpen}
             onClose={() => setTimeSlotPickerOpen(false)}
-            selectedDate={parseISO(selectedSession.session_date)}
+            selectedDate={parseISO(editSessionDate || selectedSession.session_date)}
             initialStartTime={editStartTime}
             initialEndTime={editEndTime}
             onSave={handleTimeSlotSelect}