Fix provider models per workspace (#1167)

* Scope provider snapshots by workspace

* Fix provider snapshot cwd test on Windows

packages/app/src/screens/workspace/workspace-screen.tsx

@@ -1502,8 +1502,9 @@ function WorkspaceScreenContent({
     setIsImportSheetVisible(false);
   }, []);
 
-  // Warm the global provider snapshot so the model picker is ready when opened.
+  // Warm the workspace-scoped provider snapshot so the model picker is ready when opened.
   useProvidersSnapshot(normalizedServerId, {
+    cwd: workspaceDirectory,
     enabled: isRouteFocused,
   });