fix(tools): find global .NET tools such as fsautocomplete (#497)

Global .NET tools install to `~/.dotnet/tools`, which the tool search did not look at, so an fsautocomplete installed the way its hint suggests was reported as missing unless that directory was on `PATH`. The directory is now searched after `PATH` and before the system directories.

Co-authored-by: a-rookie-of-C-language <186315048+a-rookie-of-C-language@users.noreply.github.com>

crates/ide-core/src/tool_path.rs

@@ -80,6 +80,8 @@ const USER_DIRS: &[&str] = &[
     ".cargo/bin",
     ".local/bin",
     "go/bin",
+    // `dotnet tool install --global` puts fsautocomplete, csharp-ls and friends here.
+    ".dotnet/tools",
     ".bun/bin",
     ".deno/bin",
     ".npm-global/bin",
@@ -170,6 +172,8 @@ mod tests {
         let at = |d: &str| dirs.iter().position(|p| p == Path::new(d)).unwrap();
         assert_eq!(dirs[..3], [PathBuf::from("/usr/bin"), "/opt/tools".into(), "/home/me/.asdf/shims".into()]);
         assert!(at("/home/me/.npm-global/bin") < at("/home/me/.pyenv/shims"));
+        // Global .NET tools (fsautocomplete, csharp-ls) install here, off PATH.
+        assert!(at("/home/me/.dotnet/tools") < at("/usr/local/bin"));
         assert!(at("/home/me/.local/share/mise/shims") < at("/usr/local/bin"));
         assert!(dirs.iter().all(|d| d.is_absolute()));
         let unique: HashSet<&PathBuf> = dirs.iter().collect();