Push-driven checkout diff subscriptions for changes sidebar (#24)

* Implement push-driven checkout diff subscriptions

* Remove legacy checkout diff polling RPC

* Fix checkout diff watcher coverage and fallback refresh

packages/server/src/utils/checkout-git.ts

@@ -942,7 +942,10 @@ export async function getCheckoutDiff(
   }
 
   const changes = await listCheckoutFileChanges(cwd, refForDiff);
-  changes.sort((a, b) => a.path.localeCompare(b.path));
+  changes.sort((a, b) => {
+    if (a.path === b.path) return 0;
+    return a.path < b.path ? -1 : 1;
+  });
 
   const structured: ParsedDiffFile[] = [];
   let diffText = "";