Add more options for clangd

So, while searching for better completions I found the answer in clangd itself. This change adds two new arguments for clangd:

--limit-results=500

Limit completion results to 500. This fixes the issues where we don't get most obvious completions sometimes. Default is 100, I think but even with that we miss functions so bump it to 500. This way we will be able to get all of the functions even for very big classes.

--completion-style=bundled

This option tells clangd to bundle overloads into one item so you see the item as "connect(...) [8 overloads]" which I think is much better than seeing 8 overloads which will complete to exact same thing.

These options have been there since 2018 so its safe to enable them.