Add integration tests for dbt import with local dbt project

Context

PR #5827 added dbt integration but lacks proper integration tests with an actual dbt project setup.

Description

As mentioned by @franciscojavierarceo in PR #5827, we need a lightweight local dbt project that:

• Sets up a minimal dbt project structure
• Runs dbt compile to generate manifest.json
• Tests the full feast dbt import workflow end-to-end
• Validates generated Feast objects

Acceptance Criteria

• Create test dbt project in sdk/python/tests/integration/dbt/
• Add test that compiles dbt project and imports to Feast
• Test all three data source types (bigquery, snowflake, file)
• Verify FeatureViews are created correctly
• Test tag filtering and model selection

Related

• PR feat: Add dbt integration for importing models as FeatureViews #5827
• Issue Feast <> dbt integration #3335