[BUG] Get error when aggregations exceeds the number boundary withouth pushdown in calcite

[xinyual]

What is the bug?
When use calcite without pushdown, aggregation will fail when exceeding the boundary.

How can one reproduce the bug?
Create an index like

PUT /tmp/
{
    "mappings": {
        "properties": {
            "demo": {
                "type": "short"
            }
        }
    }
}

and put two doc

POST /tmp/_doc/1
{
    "demo": 20000
}
POST /tmp/_doc/2
{
    "demo": 20000
}

Then put config like

PUT /_cluster/settings/
{
  "persistent" : {
    "plugins.calcite.enabled": true,
    "plugins.calcite.pushdown.enabled": false,
    "plugins.calcite.fallback.allowed": false
  }
}

We get error when call PPL

POST /_plugins/_ppl/
{
    "query": "source = tmp | stats sum(demo)"
}

{
  "error": {
    "reason": "There was internal problem at backend",
    "details": "java.sql.SQLException: exception while executing query: Value 40000 out of range",
    "type": "RuntimeException"
  },
  "status": 500
}

What is the expected behavior?
We can improve the precisions to allow the aggregation.

What is your host/environment?

• OS: [e.g. iOS]
• Version [e.g. 22]
• Plugins

Do you have any screenshots?
If applicable, add screenshots to help explain your problem.

Do you have any additional context?
Add any other context about the problem.