system error handling

[jngz-es]

Description

Catch all system error from agent when executing and wrap them into ErrorMessage to reply.
Tested on local testing cluster.

Some examples:

Old:
{
"error": {
"root_cause": [
{
"type": "illegal_argument_exception",
"reason": "Tool not found: VectorDBTool"
}
],
"type": "illegal_argument_exception",
"reason": "Tool not found: VectorDBTool"
},
"status": 400
}

New:
"{\n "error": {\n "reason": "Invalid Request",\n "details": "Tool not found: VectorDBTool",\n "type": "IllegalArgumentException"\n },\n "status": 400\n}"

Old:
{
"inference_results": [
{
"output": [
{
"result": """ ..."""
}
]
}
]
}

New:
{
"inference_results": [
{
"output": [
{
"name": "response",
"result": "..."
}
]
}
]
}

Issues Resolved

[List any issues this PR will resolve]

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed per the DCO using --signoff

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