Migrate from Yarn 1 to pnpm (#10465)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-authored-by: Eric Bailey <git@esb.lol>

.claude/settings.json

@@ -0,0 +1,9 @@
+{
+  "permissions": {
+    "allow": [
+      "Bash(pnpm typecheck *)",
+      "Bash(pnpm lint *)",
+      "Bash(pnpm test *)"
+    ]
+  }
+}

.claude/settings.local.json

@@ -1,9 +0,0 @@
-{
-  "permissions": {
-    "allow": [
-      "Bash(yarn typecheck *)",
-      "Bash(yarn lint *)",
-      "Bash(yarn test *)"
-    ]
-  }
-}