Extend integration tests with additional JSON output assertions

[AndreaV-Lsi]

Description

Extend integration tests to assert additional fields from the JSON output beyond exit codes and tags.

Proposed Assertions

• Checkout path — verify $repo.path matches expected relative paths (e.g., test-root-a, libs/TestA)
• Post-checkout script path — verify $pcs.scriptPath matches expected script location for configs that define scripts
• Post-checkout script configured — verify per-repo $repo.postCheckoutScript.configured is $true for repos that declare scripts
• requestedBy chain — verify the parent chain (e.g., TestA is requested by RootA, not RootB)
• selectedVersion — verify the parsed SemVer version string (e.g., 3.0.0) not just the tag