[sophiascaglioni-whoop]

Summary

Add optional database and schema keys to semantic view YAML definitions. When present, these override the global --db/--schema for that specific view's CREATE SEMANTIC VIEW statement.

semantic_views:
  - name: security_incidents_view
    database: SECURITY_DB
    schema: SEMANTIC_VIEWS
    tables:
      - {{ table('security_incidents') }}

• Parse database and schema from semantic view YAML in semantic_parser.py
• Apply per-view overrides in both sequential and parallel generation paths in generate_semantic_views.py
• Views without these fields use the global default (fully backward compatible)
• Add parser tests for new fields (present, partial, absent)

Prune limitation: sst drop --prune currently only checks the default database.schema location. Multi-location prune support is a follow-up.

Closes #258

Test plan

• parse_semantic_views includes database and schema when specified
• parse_semantic_views returns None for database/schema when not specified (backward compatible)
• Partial override (database only, no schema) works correctly
• All 1903 unit tests pass
• black clean on changed files