chore: view_cte test case

[tianzhou]

Test case to validate #106

[Copilot]

Pull Request Overview

This PR adds a test case to validate issue #106 related to CTEs (Common Table Expressions) with CASE statements in views.

• Adds a new view cte_with_case_view that combines CTEs with multiple CASE statements
• Updates test data files to reflect the addition of the fourth view
• Provides regression testing for CTE and CASE statement interaction

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
testdata/diff/create_view/add_view/plan.txt	Updated plan output to show 4 views instead of 3, including the new cte_with_case_view
testdata/diff/create_view/add_view/plan.sql	Added SQL definition for cte_with_case_view to the plan output
testdata/diff/create_view/add_view/plan.json	Added JSON entry for the new cte_with_case_view creation operation
testdata/diff/create_view/add_view/new.sql	Added the source SQL definition of cte_with_case_view with explanatory comments
testdata/diff/create_view/add_view/diff.sql	Added the diff representation of the new cte_with_case_view

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