fix: patch broken windows install (#434)

.github/workflows/ci.yml

@@ -98,6 +98,24 @@ jobs:
             echo "✓ Bundle size is acceptable"
           fi
 
+      # Test npm install flow with native shell to catch shebang issues
+      # This uses PowerShell on Windows (not Git Bash) to match real user experience
+      - name: Test npm install flow (Windows)
+        if: runner.os == 'Windows'
+        shell: pwsh
+        run: |
+          npm pack
+          npm install -g (Get-Item letta-ai-letta-code-*.tgz).FullName
+          letta --help
+
+      - name: Test npm install flow (Unix)
+        if: runner.os != 'Windows'
+        shell: sh
+        run: |
+          npm pack
+          npm install -g ./letta-ai-letta-code-*.tgz
+          letta --help
+
       - name: Headless smoke test (API)
         # Only run on push to main or PRs from the same repo (not forks, to protect secrets)
         if: ${{ github.event_name == 'push' || (github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository) }}