Refactor: Implement multi-item inventory for Pad Tracker and dynamic navigation

lib/models/cycle_entry.g.dart

@@ -19,21 +19,21 @@ class CycleEntryAdapter extends TypeAdapter<CycleEntry> {
     return CycleEntry(
       id: fields[0] as String,
       date: fields[1] as DateTime,
-      isPeriodDay: fields[2] as bool,
+      isPeriodDay: fields[2] == null ? false : fields[2] as bool,
       flowIntensity: fields[3] as FlowIntensity?,
       mood: fields[4] as MoodLevel?,
       energyLevel: fields[5] as int?,
       crampIntensity: fields[6] as int?,
-      hasHeadache: fields[7] as bool,
-      hasBloating: fields[8] as bool,
-      hasBreastTenderness: fields[9] as bool,
-      hasFatigue: fields[10] as bool,
-      hasAcne: fields[11] as bool,
-      hasLowerBackPain: fields[22] as bool,
-      hasConstipation: fields[23] as bool,
-      hasDiarrhea: fields[24] as bool,
+      hasHeadache: fields[7] == null ? false : fields[7] as bool,
+      hasBloating: fields[8] == null ? false : fields[8] as bool,
+      hasBreastTenderness: fields[9] == null ? false : fields[9] as bool,
+      hasFatigue: fields[10] == null ? false : fields[10] as bool,
+      hasAcne: fields[11] == null ? false : fields[11] as bool,
+      hasLowerBackPain: fields[22] == null ? false : fields[22] as bool,
+      hasConstipation: fields[23] == null ? false : fields[23] as bool,
+      hasDiarrhea: fields[24] == null ? false : fields[24] as bool,
       stressLevel: fields[25] as int?,
-      hasInsomnia: fields[26] as bool,
+      hasInsomnia: fields[26] == null ? false : fields[26] as bool,
       basalBodyTemperature: fields[12] as double?,
       cervicalMucus: fields[13] as CervicalMucusType?,
       ovulationTestPositive: fields[14] as bool?,
@@ -41,8 +41,8 @@ class CycleEntryAdapter extends TypeAdapter<CycleEntry> {
       cravings: (fields[27] as List?)?.cast<String>(),
       sleepHours: fields[16] as int?,
       waterIntake: fields[17] as int?,
-      hadExercise: fields[18] as bool,
-      hadIntimacy: fields[19] as bool,
+      hadExercise: fields[18] == null ? false : fields[18] as bool,
+      hadIntimacy: fields[19] == null ? false : fields[19] as bool,
       intimacyProtected: fields[29] as bool?,
       createdAt: fields[20] as DateTime,
       updatedAt: fields[21] as DateTime,