Add metric view metadata support

[shivam2680]

Description

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

Changes

• Added EnableMetricViewMetadata boolean configuration parameter to UserConfig
• Added DSN parsing support for enableMetricViewMetadata query parameter
• Added WithEnableMetricViewMetadata(bool) connector option
• Session automatically injects spark.sql.thriftserver.metadata.metricview.enabled=true when enabled
• Added 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

// Via DSN
db, err := sql.Open("databricks", "token:dapi***@host:443/path?enableMetricViewMetadata=true")

// Via connector options
connector, err := dbsql.NewConnector(
    dbsql.WithServerHostname("host"),
    dbsql.WithAccessToken("token"),
    dbsql.WithHTTPPath("/path"),
    dbsql.WithEnableMetricViewMetadata(true),
)

Testing

All unit tests pass including 2 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 Go driver, enabling getTables(), getTableTypes(), and getColumns() to return METRIC_VIEW entries when enabled. The feature is disabled by default for backward compatibility.

• Added EnableMetricViewMetadata configuration parameter with DSN parsing and connector option support
• Session automatically injects the required Spark configuration when enabled
• Added comprehensive unit tests verifying enabled and disabled states

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
internal/config/config.go	Added EnableMetricViewMetadata field to UserConfig with DSN parsing support
connector.go	Implemented session configuration injection and WithEnableMetricViewMetadata option
connector_test.go	Added tests for enabled and default disabled states

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[gopalldb]

Check suggestions from copilot