Feat/bigquery datasource [ part - 1 ]

[anoop-narang]

Add BigQuery as a native datasource

Adds BigQuery support as a native datasource, allowing users to connect to GCP BigQuery
projects, discover tables, and query them through DataFusion.

What's included

• BigQuery datasource implementation — connects via service account credentials, discovers
  tables from INFORMATION_SCHEMA, and fetches data using BigQuery Jobs API with pagination and
  batched Arrow writes
• Configurable region — supports cross-dataset discovery with a region parameter (defaults to
  "us"), or scoped discovery when a specific dataset is provided
• Inline credential support — credentials_json in the connection config is automatically
  stored as a secret and linked to the connection, matching the existing flow for Postgres
  passwords

Connection API

  {
      "name": "my_bq",
      "source_type": "bigquery",
      "config": {
          "project_id": "my-gcp-project",
          "credentials_json": "{...service account JSON...}",
          "region": "US",
          "dataset": "my_dataset"
      }
  }

Alternatively, credentials can be pre-created as a secret and referenced via secret_name or
secret_id.

[anoop-narang]

thread 'test_update_table_sync_cache_invalidation' (3845) panicked at tests/caching_catalog_tests.rs:22:10:
Failed to start Redis container: Client(PullImage { descriptor: "redis:7-alpine", err: DockerResponseServerError { status_code: 500, message: "toomanyrequests: You have reached your unauthenticated pull rate limit. https://www.docker.com/increase-rate-limit" } })