fix: return validation exit code for schema failures

[sean0407]

Summary

config test
  schema validation error -> exit 5
  other execution error -> exit 2

• Return the documented validation-failed code for schema errors.
• Add Rust mapping tests and a Windows regression case using the invalid Registry property from Exit code 5 is documented for schema validation failures but never returned (schema errors exit with 2) #1736.
• Fixes Exit code 5 is documented for schema validation failures but never returned (schema errors exit with 2) #1736.

Evidence

• Before: Exit code 5 is documented for schema validation failures but never returned (schema errors exit with 2) #1736 reports that dsc config test returns 2 for an unknown Registry property. config_test maps every invoke_test error to EXIT_DSC_ERROR; schema validation errors arrive as DscError::Schema.
• After: config_test maps DscError::Schema to the existing EXIT_VALIDATION_FAILED value (5), while other errors retain code 2. Regression tests cover both mappings and the reported input.
• git diff --check: passed. Patch policy accepted 2 files with no binary changes.

Merge Danger

Door: two-way

Blast Radius: narrow

Only the exit status for schema errors returned by dsc config test changes; other errors keep their current code.

[sean0407]

@microsoft-github-policy-service agree

[Copilot]

🟢 Approval recommended

The narrow change preserves other error mappings and includes targeted unit and regression coverage.

0 open findings

What changed in this PR

Aligns dsc config test schema-error exit codes with the documented behavior reported in #1736.

Changes:

• Returns exit code 5 for schema errors while preserving code 2 for other execution errors.
• Adds Rust mapping tests and a Windows Registry regression test.

File	Description
dsc/​tests/​dsc_config_test.tests.ps1	Tests exit code 5 for an invalid Registry property.
dsc/​src/​subcommand.rs	Maps schema errors to exit code 5 and tests both mappings.

🧠 Review effort: Balanced

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[Steve Lee (SteveL-MSFT)]

Can you change this test to use the Echo resource instead so it works cross-platform?