add workspace_lang_config_file() to helix-loader lib for consistency

helix-loader/src/lib.rs

@@ -148,6 +148,10 @@ pub fn lang_config_file() -> PathBuf {
     config_dir().join("languages.toml")
 }
 
+pub fn workspace_lang_config_file() -> PathBuf {
+    find_workspace().0.join(".helix").join("languages.toml")
+}
+
 pub fn default_log_file() -> PathBuf {
     cache_dir().join("helix.log")
 }