fix(plugins): preserve document path encoding

Keep OS-native path data intact across IPC instead of replacing non-UTF-8 bytes.

Refs #901

crates/ocs_plugin_api/src/ipc/server.rs

@@ -74,8 +74,8 @@ pub fn handle_plugin_request(
             PluginResponse::Ok
         }
         GetTabId => PluginResponse::TabId(host.tab_id()),
-        DocumentPath { tab_id } => {
-            PluginResponse::DocumentPath(host.document_path(tab_id).map(|p| p.to_string_lossy().to_string()))
-        }
+        DocumentPath { tab_id } => PluginResponse::DocumentPath(
+            host.document_path(tab_id).map(|path| path.into_os_string()),
+        ),
     }
 }