avoid yarn warnings on install

Author: ncclementi

.yarnrc.yml

@@ -1 +1,15 @@
 nodeLinker: node-modules
+
+# Patch upstream JupyterLab packages for peer validation. Does NOT install
+# anything — react/typescript are already in our package.json.
+# - testutils: declare typescript peer so Yarn sees it as satisfied by our root.
+# - settingregistry: mark react peer as optional so Yarn doesn't require
+#   services to "provide" it (we have react at root; this only relaxes the check).
+packageExtensions:
+  "@jupyterlab/settingregistry@*":
+    peerDependenciesMeta:
+      react:
+        optional: true
+  "@jupyterlab/testutils@*":
+    peerDependencies:
+      typescript: "*"