Lab: data.latest() in workflow step inputs resolved at workflow start, not at step execution time

Description

When a workflow uses data.latest() expressions in step inputs, these expressions are resolved at workflow start time rather than when the step actually executes. This means steps in later jobs receive stale data from previous runs instead of fresh data written by earlier jobs in the same workflow run.

Steps to Reproduce

Create a workflow with two jobs:
- Job 1 (create): Creates a resource (writes new data via create method)
- Job 2 (get): Gets the resource using data.latest() to resolve the identifier — depends on Job 1 succeeded
Run the workflow once — succeeds (no prior data, expressions deferred to runtime)
Run the workflow again — Job 1 succeeds, but Job 2 fails because data.latest() resolved to the OLD identifier from the previous run

Example

jobs:
  - name: create-resources
    steps:
      - name: create-vpc
        task:
          type: model_method
          modelIdOrName: test-vpc
          methodName: create

  - name: get-resources
    dependsOn:
      - job: create-resources
        condition:
          type: succeeded
    steps:
      - name: get-vpc
        task:
          type: model_method
          modelIdOrName: test-vpc
          methodName: get
          inputs:
            identifier: ${{ data.latest("test-vpc", "swamp_aws_crud_test_vpc").attributes.VpcId }}

Run 1 (no prior data): data.latest() can't resolve at start → deferred to runtime → resolves to newly created vpc-0652aafe3207ce5e6 → PASS

Run 2 (stale data from run 1 exists): data.latest() resolves at start to vpc-0652aafe3207ce5e6 (old, now deleted) → create writes new vpc-0f2acbed8e5689ccb → get step uses pre-resolved old ID → FAIL:

Resource 'vpc-0652aafe3207ce5e6' was deleted at 2026-03-07T22:56:22.253Z — run a 'create' method to re-create it first

Evidence

swamp data get test-vpc swamp_aws_crud_test_vpc --json confirms version 6 has the correct new VpcId vpc-0f2acbed8e5689ccb
But the get step received the old VpcId vpc-0652aafe3207ce5e6
get-key-pair succeeded because its identifier (KeyName: swamp_aws_crud_test_kp) is a constant that doesn't change between runs — masking the bug for that step

Expected Behavior

data.latest() expressions in step inputs should be lazily evaluated when the step executes (after dependent jobs have completed and written new data), not eagerly at workflow start time.

Impact

Any workflow that creates resources and then references them via data.latest() in later jobs will fail on second and subsequent runs. This makes CRUD test workflows non-repeatable without manually clearing data between runs.

Summary

This bug is in the workflow runtime's expression evaluation phase. data.latest() expressions in step inputs need to be deferred until step execution time rather than resolved during the pre-run evaluation pass. The fix would involve treating data.latest() (and potentially other data-referencing expressions) as runtime-resolved rather than evaluate-time-resolved when they appear in step inputs.

Found during AWS EC2 CRUD testing in /testing/aws/.

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