Removed HttpResponseHeaders class and refactored HttpRequestHeaders class into HttpHeaders. This commit merges the separate classes to represent HTTP headers into a single class, HttpHeaders. It also includes updates to the related files like HttpJavaScriptHandler and SendHttpRequestBase to reflect these changes.
* Implement Alteration types and engine
* Implement Alteration APIs
* Refactor activity work item with support for activity input
* Serialize scheduled activities as part of workflow state
* Add signal to schedule child activity
* Implement stores for plans and jobs
* Add EF Core provider
* Add Retry endpoint
* Keep root context as always active. The root context is the workflow execution context and contains persistent variable state
* Regenerate EF Core migrations
* Handle orphaned activity execution contexts
* Refactor workflow execution factory
* Enable configuring Jint from Program
* Update ModifyVariable alteration with support for type deserialization
* Use ShortGuid for identity
* Cleanup WorkflowServer host
* Update activity names and descriptions
* Rename JS functions
* Make endpoint class internal
* Pre-create workflow instance ID when dispatching workflows
* Incremental work
* Enable control over when to include full compositie root
* Cleanup
* Update WorkflowDefinitionActivity
* Implement input as variables
* Delete unused class
* Remove less common types
* Rename ExpandoObject to JSON
* Implement variable scoping
* Remove parent/child relationship from MemoryRegister
* Add support for sending input to "trigger event" endpoint
* Add support for configuring input storage driver
* Remove unused namespace imports
* Auto-register activity types when running a workflow
* Fix missing variables from containers
* Various additions and tweaks
* Fix WriteHttpResponse when no content type provided
* Bump designer version
* Return when sending response
* Remove faulty validation
