.NET Workflows - Remove Support for Code-Gen

[crickman]

Motivation and Context

Removing support for code-gen.

Description

Code-gen was never great and sufferered from interference around decision point on best solution.

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the Contribution Guidelines
• All unit tests pass, and I have added new tests where possible
• Is this a breaking change? If yes, add "[BREAKING]" prefix to the title of the PR.

[Copilot]

Pull request overview

This PR removes the .NET declarative workflow code-generation (“Eject” + T4 templates) surface area from Microsoft.Agents.AI.Workflows.Declarative, along with associated unit/integration tests that validated generated output.

Changes:

• Removed DeclarativeWorkflowBuilder.Eject(...) and the code-gen interpreter/build pipeline used to produce provider/executor scaffolding.
• Deleted the CodeGen/ T4 templates, generated .cs files, and code-gen unit tests; excluded the remaining code-gen integration test file from compilation.
• Replaced a hard [Theory(Skip=...)] with a Trait("Category","IntegrationDisabled") to align with CI filtering.

Reviewed changes

Copilot reviewed 108 out of 108 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/WorkflowActionTemplateTest.cs	Removed code-gen unit test base class.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/SetVariableTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/SetTextVariableTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/SetMultipleVariablesTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/RetrieveConversationMessagesTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/RetrieveConversationMessageTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/ResetVariableTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/ProviderTemplateTest.cs	Removed code-gen provider template unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/InvokeAzureAgentTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/GotoTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/ForeachTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/EndDialogTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/EndConversationTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/EdgeTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/DeclarativeEjectionTest.cs	Removed baseline/compile validation test for ejected code.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/CreateConversationTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/CopyConversationMessagesTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/ContinueLoopTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/ConditionGroupTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/ClearAllVariablesTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/BreakLoopTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/CodeGen/AddConversationMessageTemplateTest.cs	Removed code-gen unit test.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.IntegrationTests/Microsoft.Agents.AI.Workflows.Declarative.IntegrationTests.csproj	Excluded DeclarativeCodeGenTest.cs from compilation.
dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.IntegrationTests/DeclarativeWorkflowTest.cs	Switched from Skip to Trait("Category","IntegrationDisabled") for multi-turn tests.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/Microsoft.Agents.AI.Workflows.Declarative.csproj	Removed T4 preprocessing item group for templates.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/Interpreter/WorkflowTemplateVisitor.cs	Removed code-gen visitor that built a modeled code graph.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/Interpreter/WorkflowCodeBuilder.cs	Removed code-gen builder that emitted provider/executor source.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/DeclarativeWorkflowBuilder.cs	Removed Eject(...) public API (code generation entrypoint).
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/Snippets/FormatMessageTemplate.tt	Removed code-gen snippet template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/Snippets/EvaluateValueExpressionTemplate.tt	Removed code-gen snippet template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/Snippets/EvaluateStringExpressionTemplate.tt	Removed code-gen snippet template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/Snippets/EvaluateRecordExpressionTemplate.tt	Removed code-gen snippet template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/Snippets/EvaluateListExpressionTemplate.tt	Removed code-gen snippet template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/Snippets/EvaluateIntExpressionTemplate.tt	Removed code-gen snippet template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/Snippets/EvaluateEnumExpressionTemplate.tt	Removed code-gen snippet template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/Snippets/EvaluateBoolExpressionTemplate.tt	Removed code-gen snippet template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/Snippets/AssignVariableTemplate.tt	Removed code-gen snippet template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SetVariableTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SetVariableTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SetVariableTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SetTextVariableTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SetTextVariableTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SetTextVariableTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SetMultipleVariablesTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SetMultipleVariablesTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SetMultipleVariablesTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SendActivityTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SendActivityTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/SendActivityTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/RootTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/RootTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/RootTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/RetrieveConversationMessagesTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/RetrieveConversationMessagesTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/RetrieveConversationMessagesTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/RetrieveConversationMessageTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/RetrieveConversationMessageTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/RetrieveConversationMessageTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ResetVariableTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ResetVariableTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ResetVariableTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/QuestionTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/QuestionTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/QuestionTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ProviderTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ProviderTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ProviderTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ParseValueTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ParseValueTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ParseValueTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/InvokeAzureAgentTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/InvokeAzureAgentTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/InvokeAzureAgentTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/InstanceTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/InstanceTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/InstanceTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ForeachTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ForeachTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ForeachTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/EmptyTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/EmptyTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/EmptyTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/EditTableV2TemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/EditTableV2Template.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/EditTableV2Template.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/EdgeTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/EdgeTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/EdgeTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/DefaultTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/DefaultTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/DefaultTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/CreateConversationTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/CreateConversationTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/CreateConversationTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/CopyConversationMessagesTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/CopyConversationMessagesTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/CopyConversationMessagesTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ConditionGroupTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ConditionGroupTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ConditionGroupTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/CodeTemplate.cs	Removed code-gen base template engine implementation.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ClearAllVariablesTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ClearAllVariablesTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ClearAllVariablesTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/AddConversationMessageTemplateCode.cs	Removed code-gen template support code.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/AddConversationMessageTemplate.tt	Removed T4 template.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/AddConversationMessageTemplate.cs	Removed generated template output.
dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ActionTemplate.cs	Removed code-gen action template base class.