fix: default presensi 'belum', perbesar tombol rekap & bulk H/S/I/A/T

- Default status per jam dari 'hadir' jadi 'belum' (abu-abu '—')
- Tambah validasi skip 'belum' saat simpan
- Tombol bulk H/S/I/A/T diperbesar (w-8 h-8, border-2)
- Tombol Rekap Presensi diubah ke gradien violet-indigo
- Gradien tombol Lanjutkan & Simpan konsisten

app/Http/Controllers/AttendanceController.php

@@ -153,6 +153,9 @@ class AttendanceController extends Controller
                 if (!isset($data['student_id'], $data['lesson_hour'], $data['status'])) {
                     continue;
                 }
+                if ($data['status'] === 'belum') {
+                    continue;
+                }
                 $data['lesson_hour'] = (int) $data['lesson_hour'];
                 Attendance::updateOrCreate(
                     [