feat: add cf-edit/validate/info, epf-init/validate/add-form, erf-init tests (batches 6+7)

7 new skills covered. All 28 tests across 16 skills passing.

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

tests/skills/cases/epf-validate/valid-epf.json

@@ -0,0 +1,10 @@
+{
+  "name": "Корректная обработка проходит валидацию",
+  "preRun": [
+    {
+      "script": "epf-init/scripts/init",
+      "args": { "-Name": "Тест", "-SrcDir": "{workDir}" }
+    }
+  ],
+  "params": { "objectPath": "Тест.xml" }
+}