[clangd] Avoid using CompletionItemKind.Text for macro completions from the index (#88236)

This was fixed in https://github.com/clangd/clangd/issues/1484 for Sema
completions but the fix did not apply to index completions.

Fixes https://github.com/clangd/clangd/issues/2002

GitOrigin-RevId: 7aa371687ace40b85f04e21956e03f1e93052b56
4 files changed