feat: add role-*, subsystem-* tests (batches 4+5)

- role-compile, role-validate, role-info: 3 cases
- subsystem-compile, subsystem-validate, subsystem-info: 3 cases
- 34 tests across 22 skills, all passing

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/skills/cases/subsystem-info/_skill.json

@@ -0,0 +1,11 @@
+{
+  "script": "subsystem-info/scripts/subsystem-info",
+  "setup": "empty-config",
+  "args": [
+    { "flag": "-SubsystemPath", "from": "workPath", "field": "subsystemPath" }
+  ],
+  "snapshot": {
+    "root": "workDir",
+    "normalizeUuids": true
+  }
+}