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

lib/models/scripture.g.dart

@@ -17,11 +17,15 @@ class ScriptureAdapter extends TypeAdapter<Scripture> {
       for (int i = 0; i < numOfFields; i++) reader.readByte(): reader.read(),
     };
     return Scripture(
-      verses: (fields[0] as Map).cast<BibleTranslation, String>(),
+      verses: fields[0] == null
+          ? {}
+          : (fields[0] as Map).cast<BibleTranslation, String>(),
       reference: fields[1] as String,
       reflection: fields[2] as String?,
-      applicablePhases: (fields[3] as List).cast<String>(),
-      applicableContexts: (fields[4] as List).cast<String>(),
+      applicablePhases:
+          fields[3] == null ? [] : (fields[3] as List).cast<String>(),
+      applicableContexts:
+          fields[4] == null ? [] : (fields[4] as List).cast<String>(),
     );
   }