C# Module Requires ImplicitUsings

Right now, a C# module requires <ImplicitUsings>enable</ImplicitUsings>

Personally, I don't like implicit usings. However, when I turn them off, I get a slew of errors (shown below).

The generated code should include all it's required imports, so that developers can turn ImplicitUsings on or off as they like.

/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(119,24): error CS0246: The type or namespace name 'BinaryReader' could not be found (are you missing a using directive or an assembly reference?) [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(132,24): error CS0246: The type or namespace name 'BinaryReader' could not be found (are you missing a using directive or an assembly reference?) [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(145,24): error CS0246: The type or namespace name 'BinaryReader' could not be found (are you missing a using directive or an assembly reference?) [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(158,24): error CS0246: The type or namespace name 'BinaryReader' could not be found (are you missing a using directive or an assembly reference?) [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(52,12): error CS0246: The type or namespace name 'IEnumerable<>' could not be found (are you missing a using directive or an assembly reference?) [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(87,12): error CS0246: The type or namespace name 'IEnumerable<>' could not be found (are you missing a using directive or an assembly reference?) [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(110,28): error CS0535: 'ModuleRegistration.ClientConnected' does not implement interface member 'IReducer.Invoke(BinaryReader, IReducerContext)' [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(27,42): error CS0738: 'Message' does not implement interface member 'ITableView<Message, Module.Message>.Iter()'. 'Message.Iter()' cannot implement 'ITableView<Message, Module.Message>.Iter()' because it does not have the matching return type of 'IEnumerable<Module.Message>'. [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(58,31): error CS0738: 'User' does not implement interface member 'ITableView<User, Module.User>.Iter()'. 'User.Iter()' cannot implement 'ITableView<User, Module.User>.Iter()' because it does not have the matching return type of 'IEnumerable<Module.User>'. [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(123,27): error CS0535: 'ModuleRegistration.ClientDisconnected' does not implement interface member 'IReducer.Invoke(BinaryReader, IReducerContext)' [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(136,20): error CS0535: 'ModuleRegistration.SendMessage' does not implement interface member 'IReducer.Invoke(BinaryReader, IReducerContext)' [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(18,72): error CS0246: The type or namespace name 'Random' could not be found (are you missing a using directive or an assembly reference?) [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(149,16): error CS0535: 'ModuleRegistration.SetName' does not implement interface member 'IReducer.Invoke(BinaryReader, IReducerContext)' [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]
/home/nicholas/Projects/Games/MMO/quickstart-chat/server/SpacetimeDB.Codegen/SpacetimeDB.Codegen.Module/FFI.cs(12,25): error CS0246: The type or namespace name 'Random' could not be found (are you missing a using directive or an assembly reference?) [/home/nicholas/Projects/Games/MMO/quickstart-chat/server/StdbModule.csproj]

Start by inspecting the generated FFI.cs referenced in the compiler errors and the StdbModule.csproj with ImplicitUsings disabled. Reproduce the build to identify which required imports are absent; done means the generated C# module compiles successfully without relying on implicit usings.