[Feature] Support bacon lsp in pack-rust

### Is your feature related to a problem?

Refer to `Bacon`:
https://github.com/crisidev/bacon-ls?tab=readme-ov-file#manual
Refer to `Lazyvim`:
https://github.com/LazyVim/LazyVim/blob/main/lua/lazyvim/plugins/extras/lang/rust.lua

### Describe the new feature

Baconls is faster than rust-analyzer in analysis. I hope it can be supported.

### Additional context

_No response_

Start with the pack-rust configuration and compare the Bacon manual with LazyVim's linked Rust configuration. Confirm how bacon-ls is expected to be exposed, then verify that pack-rust supports it without disrupting the existing Rust setup.

Written by the indexing model from the issue text.