[Agent loop] Improved error reporting

### Priority

P3 - Medium (Nice to have)

### Feature Area

Designer Canvas

### Problem Statement

Opening on behalf of customer

The customer is using Logic Apps Standard for building agentic workflows. They need to have everything in VNET.

When using Agent loop and tools, they ran into runtime failures. The issues were likely due to network configurations . However, the run history did not show any error details. Please see screenshot below.

ASK - is to surface error description and enough details to help with root cause analysis. Here is a sample Run ID - 08584454549875537399167964228CU00

### Proposed Solution

Surface errors with description that help with troubleshooting

### Alternatives Considered

_No response_

### Which Logic App type(s) should this apply to?

Standard

### Additional context

_No response_

Start with the Agent loop and tools flow in the Designer Canvas, then inspect the run history for sample Run ID 08584454549875537399167964228CU00. Trace where runtime failures are presented for Logic Apps Standard and identify what error information is currently available. Done means the run history surfaces an error description and enough detail to investigate network configuration failures.

Written by the indexing model from the issue text.