fix: harden skill template contracts and scaffolding

Align scaffold slug replacement, Action manifest strict boundaries, metadata prune API, field permission validation, and task_logs readonly semantics with documented template contracts.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/test_docs_standards.py

@@ -242,6 +242,12 @@ class TestDocsStandards(unittest.TestCase):
         text = self._read("tools/README.md")
         self.assertIn("actions.json", text)
         self.assertIn("your-skill-slug", text)
+        self.assertIn("your_skill_slug", text)
+
+    def test_development_md_documents_both_slug_placeholders(self) -> None:
+        text = self._read("development/DEVELOPMENT.md")
+        self.assertIn("your-skill-slug", text)
+        self.assertIn("your_skill_slug", text)
 
     def test_schema_md_documents_data_management_contract(self) -> None:
         text = self._read("references/SCHEMA.md")