nightly-2024-09-13: feat: implement LSP code action "Implement missing members" (#6020)

# Description

## Problem

Part of #1579

## Summary

Adds a code action to add missing trait impl methods and types. Default
methods are not includeded.

Here it's working for `Add`:

![lsp-implement-missing-members-add](https://github.com/user-attachments/assets/0b3b4afc-c1bf-4c1e-9c9e-44186c7bb01b)

Here for `BigField`:

![lsp-implement-missing-members-big-field](https://github.com/user-attachments/assets/22ec63b2-9fff-4824-b9c5-2aad85cc2fce)

Here for a complex type in Aztec-Packages:

![lsp-implement-missing-members-aztec](https://github.com/user-attachments/assets/de822bcc-1397-456a-8175-58613ffa1f0e)

## Additional Context

I found this code action in Rust very useful! It saves a lot of time,
plus there's no need to copy-paste :-)

## Documentation

Check one:
- [x] No documentation needed.
- [ ] Documentation included in this PR.
- [ ] **[For Experimental Features]** Documentation to be submitted in a
separate PR.

# PR Checklist

- [x] I have tested the changes locally.
- [x] I have formatted the changes with [Prettier](https://prettier.io/)
and/or `cargo fmt` on default settings.