Support classic index definitions

[g31pranjal]

This PR adds support for defining Index using the classic Index definitions.

To add support for Filtered Indexes and other indexes, like Aggregate Indexes, and Bitmap Indexes, the classic Index definition also support defining indexes over views.

[github-actions]

📊 Metrics Diff Analysis Report

Summary

• New queries: 22
• Dropped queries: 0
• Plan changed + metrics changed: 0
• Plan unchanged + metrics changed: 0

ℹ️ About this analysis

This automated analysis compares query planner metrics between the base branch and this PR. It categorizes changes into:

• New queries: Queries added in this PR
• Dropped queries: Queries removed in this PR. These should be reviewed to ensure we are not losing coverage.
• Plan changed + metrics changed: The query plan has changed along with planner metrics.
• Metrics only changed: Same plan but different metrics

The last category in particular may indicate planner regressions that should be investigated.

New Queries

Count of new queries by file:

• yaml-tests/src/test/resources/alternate-index-syntax.metrics.yaml: 22