duckdb: Show catalog (database) where applicable (e.g. Motherduck)

[wlach]

What type of PR is this?

• Bug Fix
• Refactor
• Feature
• New Query Runner (Data Source)
• New Alert Destination
• Other

Description

This PR fixes the DuckDB query runner's schema browser to properly display database/catalog names when using MotherDuck or attached databases.

When connecting to MotherDuck (e.g., using md:?motherduck_token={access_token}), the schema browser was only showing schema.table (e.g., kaggle.movies) instead of the full three-part name database.schema.table (e.g., sample_data.kaggle.movies). Updated the schema retrieval query to include table_catalog from information_schema.tables and construct the full table name accordingly.

The implementation handles two use cases:

• Local databases (memory, temp, system): Continue to show 2-part names like main.users to avoid unnecessary clutter
• MotherDuck/attached databases: Shows 3-part names like sample_data.kaggle.movies to properly distinguish between databases

Compatible with all DuckDB versions that support the information_schema.tables view with table_catalog column (including the version currently used by redash).

Implementation note: the code (and parts of this pull request description) were written by Claude 4.5 Sonnet, with human intervention and review.

How is this tested?

• Unit tests (pytest, jest)
• E2E Tests (Cypress)
• Manually
• N/A

Unit Tests Added:

• test_motherduck_catalog_included: Verifies that non-default catalogs include the catalog name in table names
• Updated existing tests to include table_catalog field in mock data

Manual Testing:

• Tested with MotherDuck connection using md:?motherduck_token={access_token}
• Verified schema browser shows full database names (e.g., sample_data.kaggle.movies)
• Verified local DuckDB databases continue to show clean 2-part names (e.g., main.users)
• Confirmed queries execute correctly against both MotherDuck and local databases

Related Tickets & Documents

N/A

Mobile & Desktop Screenshots/Recordings (if there are UI changes)

No UI changes but FWIW here's a screenshot of the support using a connection to Motherduck and its default sample data:

[cubic-dev-ai]

No issues found across 2 files