fix: preserve cc-sdd package-lock.json for CI reproducibility

Add exception in .gitignore to keep tools/cc-sdd/package-lock.json
This ensures reproducible builds in CI/CD pipelines.

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Co-Authored-By: Claude <noreply@anthropic.com>

Author: 2 people

.gitignore

@@ -45,6 +45,9 @@ build/
 package-lock.json
 yarn.lock
 
+# Exceptions for CI reproducibility
+!tools/cc-sdd/package-lock.json
+
 # Environment variables
 .env
 .env.local