GRM-35: fix: release push permission and notify_failure label IDs

Fix two issues found during release workflow testing.

Closes GRM-35

src/gitea_runner_manager/api_clients.py

@@ -105,8 +105,12 @@ class GiteaClient:
                 return None
         return self.create_label(name, color, description)
 
-    def create_issue(self, title: str, body: str = "", labels: list[str] | None = None) -> dict[str, Any]:
-        """Create a new issue in the repository."""
+    def create_issue(self, title: str, body: str = "", labels: list[int] | None = None) -> dict[str, Any]:
+        """Create a new issue in the repository.
+
+        Args:
+            labels: List of label IDs (integers, not names).
+        """
         payload: dict[str, Any] = {"title": title, "body": body}
         if labels:
             payload["labels"] = labels