Feat(lsp): Add rename functionality for CTEs in vscode

[themisvaltinos]

This update adds CTE renaming (F2) to the SQLMesh LSP server, letting users rename CTEs and their references with proper scope handling. Still to do:

• Handle CTE with specific column reference or star [ Tackled here: Fix(lsp): Extend support for table references with columns #4763 ]
• Add end to end test

[benfdking]

WITH A AS (
  SELECT 1 AS B
)

SELECT A.B AS C FROM A WHERE A.B > 2

SELECT A.* FROM A WHERE A.B > 2

^ Do the two As in A.B get renamed.

[themisvaltinos]

^ Do the two As in A.B get renamed.

thanks after #4763 now yes they do as they're picked up as references. added tests for it and end to end for rename functionality in general

[Copilot]

Pull Request Overview

Adds rename support for Common Table Expressions (CTEs) in the SQLMesh LSP server and VSCode extension, including UI interactions, preview, and document highlights.

• Implements prepare_rename, rename_symbol, and get_document_highlights in sqlmesh/lsp/rename.py and wires up LSP handlers in sqlmesh/lsp/main.py.
• Expands end-to-end Playwright tests in vscode/extension/tests/rename_cte.spec.ts to cover rename, cancel, and preview flows.
• Adds Python LSP unit tests (tests/lsp/test_rename_cte.py and tests/lsp/test_document_highlight.py) to verify rename and highlight behavior.

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
sqlmesh/lsp/rename.py	Implements core CTE rename and highlight logic
sqlmesh/lsp/main.py	Registers LSP handlers for prepareRename, rename, and highlight
vscode/extension/tests/rename_cte.spec.ts	Adds UI tests for rename, cancel, preview, and references
tests/lsp/test_rename_cte.py	Unit tests for prepareRename and renameSymbol flows
tests/lsp/test_document_highlight.py	Unit tests for document highlight on CTE symbols

Comments suppressed due to low confidence (2)

sqlmesh/lsp/rename.py:49

• Hardcoding the placeholder to 'cte_name' may confuse users; consider using the actual CTE identifier (e.g., extract the text under the target_range) so the rename UI shows the current name.

            return PrepareRenameResult_Type1(range=target_range, placeholder="cte_name")

vscode/extension/tests/rename_cte.spec.ts:61

• [nitpick] This test only verifies the definition rename; you may want to also assert that usage occurrences (e.g. in the FROM clause) were updated to 'new_marketing' for full coverage.

    await expect(window.locator('text=WITH new_marketing AS')).toBeVisible()