fix(tests): update cluster health test mock to use correct response format

The health.py action expects response in format {"data": {...}} but the
tests were mocking {"health": {...}}. This caused the test to fail because
the code would not find any health data and mark all checks as unavailable.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: dittops

services/budpipeline/tests/actions/cluster/test_cluster_actions.py

@@ -73,7 +73,7 @@ async def test_execute_success(self) -> None:
             "invoke_service",
             new_callable=AsyncMock,
             return_value={
-                "health": {
+                "data": {
                     "nodes": {"healthy": True, "message": "All nodes ready"},
                     "api": {"healthy": True, "message": "API server responding"},
                 }
@@ -97,7 +97,7 @@ async def test_execute_degraded(self) -> None:
             "invoke_service",
             new_callable=AsyncMock,
             return_value={
-                "health": {
+                "data": {
                     "nodes": {"healthy": False, "message": "2 nodes not ready"},
                     "api": {"healthy": True, "message": "API server responding"},
                 }