10802: Allow clients to configure the global workspace search limit r=Veykril a=knutwalker
Playing around with [helix](https://helix-editor.com) I realized that the global worksapce symbol search works different compared to vs-code.
Helix requires all possible symbols in one query and does no subsequent refinement searched.
This PR adds a configuration option to override the default search limit with the default being the currently hardocded value.
Helix users can increment this limit for their instance with a config like
```toml
[[language]]
name = "rust"
language-server = { command = "rust-analyzer" }
[language.config]
workspace = { symbol = { search = { limit = 65536 }}}
```
Other editors are not affected by this change.
Co-authored-by: Paul Horn <dev@knutwalker.engineer>
bc0825d135