project: Fine-grained language server management (#24038)

Closes #ISSUE
https://github.com/zed-industries/zed/pull/23804
Release Notes:

- Improved detection of project roots for use by language servers.

Closes #ISSUE

Release Notes:

- N/A *or* Added/Fixed/Improved ...

---------

Co-authored-by: smit <0xtimsb@gmail.com>
Co-authored-by: Henrikh Kantuni <henrikh.kantuni@gmail.com>
Co-authored-by: Caleb! <48127194+kaf-lamed-beyt@users.noreply.github.com>
Co-authored-by: Marshall Bowers <git@maxdeviant.com>
Co-authored-by: Kirill Bulatov <kirill@zed.dev>
Co-authored-by: Agus Zubiaga <agus@zed.dev>
Co-authored-by: Danilo <danilo@zed.dev>
Co-authored-by: Nate Butler <iamnbutler@gmail.com>

crates/zed/src/zed.rs

@@ -1711,7 +1711,7 @@ mod tests {
             .fs
             .as_fake()
             .insert_tree(
-                "/root",
+                path!("/root"),
                 json!({
                     "a": {
                     },
@@ -1721,7 +1721,7 @@ mod tests {
 
         cx.update(|cx| {
             open_paths(
-                &[PathBuf::from("/root/a/new")],
+                &[PathBuf::from(path!("/root/a/new"))],
                 app_state.clone(),
                 workspace::OpenOptions::default(),
                 cx,