finish get-character implementation

OwnChar/Data/IDataManager.cs

@@ -16,4 +16,8 @@ public interface IDataManager
     // Group management
     abstract UserProfile? GetOwner(Group group);
     abstract IEnumerable<UserProfile>? GetMembers(Group group);
+
+    // Character management
+    abstract IEnumerable<Character>? GetCharacters(Group group);
+    abstract IEnumerable<Character>? GetCharacters(UserProfile profile);
 }

OwnChar/Data/IDataProvider.cs

@@ -26,4 +26,6 @@ public interface IDataProvider
     abstract IEnumerable<UserProfile>? GetGroupMembers(Group group);
     abstract UserProfile? GetOwner(Group group);
     abstract UserProfile? GetOwner(Character character);
+    abstract IEnumerable<Character>? GetCharacters(Group group);
+    abstract IEnumerable<Character>? GetCharacters(UserProfile jprofile);
 }

OwnChar/Data/Managers/DefaultDataManager.cs

@@ -87,4 +87,14 @@ public class DefaultDataManager : IDataManager
         DataProvider.Delete(account);
         return true;
     }
+
+    public IEnumerable<Character>? GetCharacters(Group group)
+    {
+        return DataProvider.GetCharacters(group);
+    }
+
+    public IEnumerable<Character>? GetCharacters(UserProfile profile)
+    {
+        return DataProvider.GetCharacters(profile);
+    }
 }

OwnChar/Data/Providers/JsonFile/JsonFileDataProvider.cs

@@ -221,4 +221,18 @@ public class JsonFileDataProvider : IDataProvider
             return jcharacter.Owner;
         return null;
     }
+
+    public IEnumerable<Character>? GetCharacters(Group group)
+    {
+        if (group is JsonGroup jgroup)
+            return jgroup.Characters;
+        return null;
+    }
+
+    public IEnumerable<Character>? GetCharacters(UserProfile profile)
+    {
+        if (profile is UserProfile jprofile)
+            return JsonFile.Characters.Where(n => n.Owner == profile);
+        return null;
+    }
 }