feat(cloudformation): provision AWS::StepFunctions::StateMachine

[walker-luke]

Summary

CloudFormationResourceProvisioner has handlers for ~30 resource types but no case for AWS::StepFunctions::StateMachine. Templates containing one currently fall through to the default branch in provision(...), which stubs a placeholder physical id, sets Arn to arn:aws:stub:::<logical-id>, and reports CREATE_COMPLETE without ever calling StepFunctionsService.

The state machine therefore does not exist in the SFN store after a stack create. Downstream resources that depend on it (e.g. AWS::Pipes::Pipe with a Step Functions target) deploy successfully but fail at runtime with State machine does not exist (AwsException) the first time the pipe tries to invoke its target.

Change

Add a provisioner that delegates to the existing StepFunctionsService.createStateMachine:

• Resolves StateMachineName (auto-generates from logical id when absent, matching the Pipe/Lambda pattern).
• Resolves DefinitionString and applies DefinitionSubstitutions - the same ${Var} replacement CloudFormation performs server-side before handing the definition to Step Functions.
• Resolves RoleArn, StateMachineType, and Tags (via the existing parseCfnTags helper).
• Sets PhysicalId to the canonical ARN (matching real AWS Ref semantics) and exposes Arn + Name attributes for Fn::GetAtt.

Wires deletion through StepFunctionsService.deleteStateMachine.

Test plan

Adds CloudFormationIntegrationTest#createStack_stepFunctionsStateMachineResolvesDefinitionSubstitutionsAndIsDeletable, which:

• Creates a stack containing an IAM role plus an AWS::StepFunctions::StateMachine with a DefinitionSubstitutions map referencing `{Marker}`.
• Asserts DescribeStateMachine returns the canonical ARN, the resolved role, and a definition where ${Marker} has been replaced (and no placeholder remains).
• Asserts the stack's Outputs expose the canonical ARN via Ref and the name via Fn::GetAtt.
• Deletes the stack and asserts DescribeStateMachine then returns StateMachineDoesNotExist.

Verified locally:

• ./mvnw test -Dtest=CloudFormationIntegrationTest - 77/77 pass
• ./mvnw test -Dtest='StepFunctions*Test' - 68/68 pass

Notes

• No changes to StepFunctionsService, the SFN wire protocol, or any other resource handler.
• LoggingConfiguration and TracingConfiguration properties are accepted on the input but not persisted, matching how other Floci provisioners treat operationally‑irrelevant emulator properties today.

[hectorvent]

Hi @walker-luke,

Thanks for the PR. It is a solid fix.
Please take a look at the conflicts.