Add SessionStart hook so tests/typecheck work in web sessions

.claude/hooks/session-start.sh

@@ -0,0 +1,24 @@
+#!/bin/bash
+#
+# SessionStart hook for Claude Code on the web.
+#
+# A fresh remote session starts with no node_modules, so yarn typecheck,
+# yarn test and yarn build all fail (e.g. "tsc: not found", "vite: not found")
+# until dependencies are installed. This hook installs them, and fetches the
+# Playwright browser build that the pinned @playwright/test version expects so
+# the test suite can run.
+#
+# Runs synchronously so dependencies are guaranteed ready before the agent
+# starts. Idempotent and non-interactive.
+set -euo pipefail
+
+cd "$CLAUDE_PROJECT_DIR"
+
+# Install JS dependencies (uses yarn's cache; safe to re-run).
+yarn install
+
+# Install the Chromium build that the pinned Playwright version needs so
+# `yarn test` works. Skipped automatically if already present.
+yarn playwright install chromium
+
+echo "session-start hook complete: dependencies and Playwright browser ready"

.claude/settings.json

@@ -0,0 +1,14 @@
+{
+  "hooks": {
+    "SessionStart": [
+      {
+        "hooks": [
+          {
+            "type": "command",
+            "command": "$CLAUDE_PROJECT_DIR/.claude/hooks/session-start.sh"
+          }
+        ]
+      }
+    ]
+  }
+}