956 bug modifiedat createdat brake compatibility

[kuh0005]

This pull request standardizes the naming and usage of created and modified date properties across multiple classes and interfaces in the codebase. The changes replace previous Created, Modified, CreatedAt, and ModifiedAt properties with consistently named _Created and _Modified properties, ensuring uniformity in how creation and modification timestamps are handled and displayed. Updates are made to interfaces, entity classes, repositories, UI components, and business logic to reflect this new convention.

Core property renaming and standardization:

• The IBrowsableDataObject interface now uses DateTime _Created and DateTime _Modified instead of CreatedAt and ModifiedAt, removing nullable types and legacy property names. (src/base/src/AXOpen.Base.Abstractions/Data/IBrowsableDataObject.cs)
• All implementing classes (PersistentRecord, AxoDataEntity, Group, User) have been updated to use _Created and _Modified properties, removing old property names and compatibility layers. (src/data/src/AXOpen.Data/DataPersistentExchange/PersistentRecord.cs, src/data/src/AXOpen.Data/Entity/Pocos/AxoDataEntity.cs, src/security/src/AXOpen.Security/Entities/Group.cs, src/security/src/AXOpen.Security/Entities/User.cs) [1] [2] [3] [4]

Repository and business logic updates:

• The RepositoryBase class now sets _Created and _Modified properties when creating or updating entities, replacing previous usage of CreatedAt and ModifiedAt. (src/base/src/AXOpen.Base.Abstractions/Data/RepositoryBase.cs) [1] [2]
• Group and user entity constructors and update methods now initialize and update _Created and _Modified properties consistently. (src/security/src/AXOpen.Security/Entities/Group.cs, src/security/src/AXOpen.Security/Entities/User.cs, src/security/src/AXOpen.Security/Stores/UserStore.cs) [1] [2] [3]

UI and display changes:

• Razor pages for group and user management now reference _Created and _Modified properties for display, ensuring UI reflects the updated property names. (src/Security/src/AXOpen.Security.Blazor/Pages/GroupManagement.razor, src/Security/src/AXOpen.Security.Blazor/Pages/UserManagement.razor) [1] [2] [3]

Role and group management logic:

• Role group management methods update group modification timestamps using the new _Modified property. (src/security/src/AXOpen.Security/RoleGroupManager.cs) [1] [2] [3]

These changes collectively improve code clarity and consistency regarding entity timestamp handling throughout the application.