feat(ir): add typed helper for CopyFiles@2

[github-actions]

Summary

Adds a typed factory function for CopyFiles@2 to the ado-aw IR.

Motivation

Previously, any code that needed to emit a CopyFiles@2 step had to hand-craft
TaskStep::new("CopyFiles@2", ...) with raw string inputs. This PR introduces a
well-typed copy_files_step() helper that makes required inputs explicit at the
call site and provides a clear, self-documenting API consistent with the patterns
already established for publish_test_results_step.

Changes

• src/compile/ir/tasks.rs: copy_files_step(contents, target_folder) factory function with full doc comment covering all 8 optional inputs
• src/compile/ir/tasks.rs: 3 unit tests covering required inputs, optional SourceFolder, and optional boolean flags

ADO Task Reference

• Task: CopyFiles@2
• Docs: (https://learn.microsoft.com/en-us/azure/devops/pipelines/tasks/reference/copy-files-v2)
• Required inputs: Contents, TargetFolder
• Optional inputs: SourceFolder, CleanTargetFolder, OverWrite, flattenFolders, preserveTimestamp, retryCount, delayBetweenRetries, ignoreMakeDirErrors

Validation

• cargo build --all-targets
• cargo test — all 1856+ tests pass, 3 new tests for copy_files_step
• cargo clippy --all-targets --all-features --workspace -- -D warnings

---

Created by the ado-task-ir-contributor workflow.

Warning

Firewall blocked 2 domains

The following domains were blocked by the firewall during workflow execution:

• spsprodeus21.vssps.visualstudio.com
• spsprodweu4.vssps.visualstudio.com

To allow these domains, add them to the network.allowed list in your workflow frontmatter:

network:
  allowed:
    - defaults
    - "spsprodeus21.vssps.visualstudio.com"
    - "spsprodweu4.vssps.visualstudio.com"

See Network Configuration for more information.

Generated by ADO Task IR Contributor · 642.2 AIC · ⌖ 18.1 AIC · ⊞ 35.3K · ◷

[jamesadevine]

@copilot resolve merge conflicts

[Copilot]

@copilot resolve merge conflicts

Done. Merged origin/main into this branch and resolved the conflict in src/compile/ir/tasks.rs by keeping both copy_files_step (this PR) and docker_installer_step (added on main via #1015). Commit: 50b3cf7.