Fix IndexOutOfBoundsException in Arrow Metadata Access for DDL Statements (databricks#1186)

## Description

Fixed `IndexOutOfBoundsException` that occurs when executing DDL
statements (e.g., `CREATE DATABASE`) using the Thrift protocol. The bug
manifests when there's a mismatch between the number of Thrift column
descriptors and Arrow schema fields.

### Root Cause

When executing DDL statements, the Databricks server behavior is:
- **Thrift Protocol**: Returns column descriptors including a "Result"
status column (1 column)
- **Arrow Schema**: Returns an empty schema with 0 fields (no actual
data)
- **The Bug**: Code attempted to access `arrowMetadata[0]` without
checking if the list was empty

This mismatch caused `IndexOutOfBoundsException` when the driver tried
to access arrow metadata at index 0 of an empty list.

### Debug Evidence

**TColumnDesc (Thrift)**:
```
Column[0]:
  name: Result
  type: STRING_TYPE
  position: 1
  Full TColumnDesc: TColumnDesc(columnName:Result, typeDesc:TTypeDesc(...), position:1, comment:)
```

**Arrow Schema**:
```
Arrow schema bytes length: 72
Deserialized Arrow schema, field count: 0  ← Empty!
Arrow metadata list: size=0
```

### Changes Made

Added bounds checking in two locations where arrow metadata is accessed:

1. **`ArrowUtil.java:247`** - Used by `StreamingInlineArrowResult`
2. **`DatabricksResultSetMetaData.java:195`** - Used for result set
metadata construction

**Before:**
```java
String columnArrowMetadata =
    arrowMetadata != null ? arrowMetadata.get(columnIndex) : null;
```

**After:**
```java
String columnArrowMetadata =
    arrowMetadata != null && columnIndex < arrowMetadata.size()
        ? arrowMetadata.get(columnIndex)
        : null;
```

## Testing

### Manual Testing

**Test Case**: Execute CREATE DATABASE statement
```java
String sqlQuery = "CREATE DATABASE IF NOT EXISTS hive_metastore.test_db";
boolean hasResultSet = stmt.execute(sqlQuery);
```


**Before Fix**: `IndexOutOfBoundsException: Index 0 out of bounds for
length 0`
**After Fix**: Executes successfully, returns `hasResultSet=false`

## Additional Notes to the Reviewer

NO_CHANGELOG=true

Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: sreekanth-db

src/main/java/com/databricks/jdbc/api/impl/DatabricksResultSetMetaData.java

@@ -192,7 +192,9 @@ public DatabricksResultSetMetaData(
           TColumnDesc columnDesc = resultManifest.getSchema().getColumns().get(columnIndex);
 
           String columnArrowMetadata =
-              arrowMetadata != null ? arrowMetadata.get(columnIndex) : null;
+              arrowMetadata != null && columnIndex < arrowMetadata.size()
+                  ? arrowMetadata.get(columnIndex)
+                  : null;
           ColumnInfo columnInfo = getColumnInfoFromTColumnDesc(columnDesc, columnArrowMetadata);
           int[] precisionAndScale = getPrecisionAndScale(columnInfo);
           int precision = precisionAndScale[0];

src/main/java/com/databricks/jdbc/common/util/ArrowUtil.java

@@ -245,7 +245,9 @@ public static List<ColumnInfo> getColumnInfoList(TGetResultSetMetadataResp resul
     for (int columnIndex = 0; columnIndex < columns.size(); columnIndex++) {
       TColumnDesc tColumnDesc = columns.get(columnIndex);
       String columnArrowMetadata =
-          arrowMetadataList != null ? arrowMetadataList.get(columnIndex) : null;
+          arrowMetadataList != null && columnIndex < arrowMetadataList.size()
+              ? arrowMetadataList.get(columnIndex)
+              : null;
       columnInfos.add(getColumnInfoFromTColumnDesc(tColumnDesc, columnArrowMetadata));
     }
     return columnInfos;