[clang-tools-extra] [clangd] Add support for textDocument/rangesFormatting (LSP 3.18) (PR #80180)

[Tom Praschan via cfe-commits]

tom-anders wrote:

> ping - [Support for textDocument/rangesFormatting is about to be merged into neovim](https://github.com/neovim/neovim/pull/27323), so we'll soon have at least two editors (nvim, vscode) with support for this

Update: neovim PR has been merged

https://github.com/llvm/llvm-project/pull/80180