Connections Pane: BigQuery Support

[dfalbel]

Addresses #10431

A connection can be created with:

from google.cloud import bigquery

public = bigquery.Client(project="bigquery-public-data")
%connection_show public

The client can be installed with

pip install google-cloud-bigquery

Authentication is automatic if you download the gcloud CLI, and then run:

gcloud auth login

Release Notes

New Features

• Added Google BigQuery support for the connections pane for Python (Connections Pane: Google BigQuery python connector #10431).

Bug Fixes

• N/A

QA Notes

@:connections

[github-actions]

E2E Tests 🚀
This PR will run tests tagged with: @:critical @:connections

^{readme  valid tags}

[Copilot]

Pull Request Overview

This PR adds support for Google BigQuery connections to the Connections Pane, enabling users to browse datasets, tables, and views from BigQuery projects through the Positron interface.

• Implements GoogleBigQueryConnection class with methods to list datasets/tables, retrieve field information, and preview data
• Adds BigQueryConnectionInspector to detect and validate BigQuery client instances
• Includes comprehensive test suite covering connection registration, object listing, field inspection, and data preview

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
extensions/positron-python/python_files/posit/positron/connections.py	Adds GoogleBigQueryConnection class implementing the Connection interface for BigQuery clients, with support for dataset/table hierarchy and data previewing
extensions/positron-python/python_files/posit/positron/inspectors.py	Adds BigQueryConnectionInspector to identify and validate BigQuery client connections in the variables pane
extensions/positron-python/python_files/posit/positron/tests/test_connections.py	Adds comprehensive test suite for BigQuery connection functionality including object listing, field inspection, and preview capabilities