fix: Use build:client for contract test utils in node-client CI

build:client compiles tsconfig.client.json which already includes dist/index.js
and dist/client.js without pulling in the server-side TestHook that depends on
@launchdarkly/js-server-sdk-common (not built in the node-client CI pipeline).

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

Author: joker23

.github/workflows/node-client.yml

@@ -36,7 +36,7 @@ jobs:
           ELECTRON_SKIP_BINARY_DOWNLOAD: '1'
         run: yarn workspace @launchdarkly/node-client-sdk-contract-tests install --no-immutable
       - name: Build shared contract test utils
-        run: yarn workspace @launchdarkly/js-contract-test-utils build:no-server
+        run: yarn workspace @launchdarkly/js-contract-test-utils build:client
       - name: Build the test service
         run: yarn workspace @launchdarkly/node-client-sdk-contract-tests build
       - name: Launch the test service in the background