* refactor: Rename AggregateTurnMessagesExecutor
* feat: Rework Agent Hosting for Configurability and HIL support
* Adds support for selecting whether updates and/or full responses are
emitted to events
* Adds support for HIL/FunctionCalls (including interception)
* Implements internal support for ExternalRequests from any executor
(not just RequestPort)
* test: Add tests for new AIAgentHostExecutor functionality
* feat: Unify non-Handoff Agent Hosting
* doc: More explicit documentation for `overwrite` in RouteBuilder
* refactor: remove unused internals
* feat: Execution Mode for sharing a workflow among concurrent runs
* feat: Update WorkflowHostAgent to support concurrent execution
* Also update AsAgent APIs to support injecting a CheckpointManager and an IWorkflowExecutionEnvironment
* fix: Make Read logic consistent in DeclarativeWorkflowContext