[ZEPPELIN-6408] Modernize BigQuery Interpreter with google-cloud-bigquery client

[jongyoul]

What is this PR for?

The current BigQuery interpreter uses the legacy google-api-services-bigquery library, which is outdated and lacks modern features like the Storage Read API. This PR updates the interpreter to use the modern google-cloud-bigquery Cloud Client Library.

Key improvements:

• Updated core dependencies to google-cloud-bigquery (v2.38.0).
• Simplified query execution and result iteration using modern APIs.
• Enhanced authentication flow:
  • Supports Application Default Credentials (ADC).
  • Added a fallback mechanism to prompt for Service Account JSON via Zeppelin's GUI if ADC is unavailable.
• Improved error handling and job management (cancellation support).

What type of PR is it?

Improvement, Refactoring

Todos

• - Update bigquery/pom.xml with modern Google Cloud dependencies.
• - Refactor BigQueryInterpreter.java to use the new client library.
• - Implement fallback authentication via z.input GUI.
• - Update and verify BigQueryInterpreterTest against a live GCP environment.

What is the Jira issue?

• ZEPPELIN-6408

How should this be tested?

• Automated Tests: Updated BigQueryInterpreterTest to use the new client. Verified against a live GCP project using public datasets.
• Manual Verification:
  1. Configure a BigQuery interpreter in Zeppelin.
  2. Run a query. It should automatically use ADC from the environment.
  3. If ADC is missing, it should display an input box asking for a Service Account JSON. Paste a valid JSON key and run again to verify successful authentication.

Screenshots (if appropriate)

(Not applicable for this library update, but functional verification confirmed via logs)

Questions:

• Does the license files need to update? No.
• Is there breaking changes for older versions? No, existing properties are maintained.
• Does this needs documentation? No major documentation changes required, but GUI fallback is a new UX feature.

[Copilot]

Pull request overview

Updates Zeppelin’s BigQuery interpreter to use the modern google-cloud-bigquery Java client library, replacing the legacy BigQuery API client and documenting the new authentication behavior.

Changes:

• Refactors BigQueryInterpreter to execute queries and iterate results using google-cloud-bigquery.
• Adds an authentication fallback flow that prompts for a Service Account JSON key when ADC isn’t available.
• Updates BigQuery interpreter docs/README and adjusts the integration test context setup.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 14 comments.

Show a summary per file

File	Description
bigquery/src/main/java/org/apache/zeppelin/bigquery/BigQueryInterpreter.java	Migrates execution/auth/cancel logic to google-cloud-bigquery and adds GUI-based SA JSON fallback.
bigquery/pom.xml	Replaces legacy Google API deps with google-cloud-bigquery and updates Guava dependency.
bigquery/src/test/java/org/apache/zeppelin/bigquery/BigQueryInterpreterTest.java	Updates resource loading and sets AuthenticationInfo on the context.
docs/interpreter/bigquery.md	Updates user-facing docs for new client + authentication modes and refreshes examples.
bigquery/README.md	Updates module README with new auth/config/test instructions.

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