Expose DbContext._options through public property

[MaceWindu]

Created on request from @divega #11657 (comment)

linq2db integration with EF.Core needs access to DbContextOptions for specific DbContext instance or more precisely, to DbContextOptions.Extensions collection.

Current implementation uses reflection to read private field _options: https://github.com/linq2db/linq2db.EntityFrameworkCore/blob/master/Source/LinqToDB.EntityFrameworkCore/LinqToDBForEFToolsImplDefault.cs#L300

[ajcvickers]

@MaceWindu For what reason do you need DbContextOptions? The reason I ask is because it is not intended that these options be obtained and used directly. Instead, the way to access options is from registered options extensions. For example:

var optionsExtension = context
    .GetService<IDbContextOptions>()
    .FindExtension<CoreOptionsExtension>();

[MaceWindu]

I think you are right here. Will check and close this issue, if it will help

[MaceWindu]

ok, we don't need it. Thank you :)