While tinkering with my local setup, I noticed that on neovim nightly
it's sufficient to enable native inlay_hint functionality in LspAttach
autocmd.
Here's relevant part from my config:

    vim.api.nvim_create_augroup('LspWatchers', { clear = true })
    vim.api.nvim_create_autocmd('LspAttach', {
      group = 'LspWatchers',
      callback = function(args)
        if not (args.data and args.data.client_id) then
          return
        end

        local bufnr = args.buf

The idea behind this change is to separate lspconfig call
and preparation for the call. This would allow users to
choose whether to skip clangd setup entirely in favor of this
plugin, or incorporate it by preparing and using returned configuration
in their own setup routine.

---

> this lets the user call `require("clangd_extensions").prepare()` and then lspconfig's setup whenever they want?

That's exactly it. I'd updated the README to mention and explain `prepare` usage.

 README.md                      | 11 ++++--
 lua/clangd_extensions/init.lua | 65 ++++++++++++++++++++++------------
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