Add metric view metadata support

[shivam2680]

Description

This PR adds support for metric view metadata in the Databricks SQL Node.js driver, following the JDBC driver implementation.

Changes

• Added enableMetricViewMetadata optional boolean to ConnectionOptions interface
• Added enableMetricViewMetadata optional boolean to ClientConfig interface
• Updated DBSQLClient.connect() to store the configuration
• Updated DBSQLClient.openSession() to inject spark.sql.thriftserver.metadata.metricview.enabled=true when enabled
• Added 6 comprehensive unit tests

Behavior

When enableMetricViewMetadata=true:

• getTables() and getTableTypes() will include METRIC_VIEW entries
• getColumns() will return measure columns with <data_type> measure format in TYPE_NAME

Usage

const client = new DBSQLClient();

await client.connect({
  host: 'your-workspace.cloud.databricks.com',
  path: '/sql/protocolv1/o/...',
  token: 'dapi***',
  enableMetricViewMetadata: true
});

const session = await client.openSession();

Testing

All 437 unit tests pass including 6 new tests for this feature.

Backward Compatibility

Feature is disabled by default - fully backward compatible.

[Copilot]

Pull Request Overview

This PR adds support for metric view metadata in the Databricks SQL Node.js driver by introducing a new configuration option that enables retrieval of metric view information through metadata methods. When enabled, the driver injects a Spark configuration parameter during session creation.

Key Changes:

• Added enableMetricViewMetadata configuration option to connection and client interfaces
• Modified session opening logic to conditionally inject the Spark configuration parameter
• Added comprehensive test coverage for the new feature

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
lib/contracts/IDBSQLClient.ts	Added enableMetricViewMetadata optional property to ConnectionOptions interface
lib/contracts/IClientContext.ts	Added enableMetricViewMetadata optional property to ClientConfig interface
lib/DBSQLClient.ts	Stored configuration and injected session parameter when metric view metadata is enabled
tests/unit/DBSQLClient.test.ts	Added 6 unit tests covering configuration storage, parameter injection, and user configuration preservation

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