debug: Add working directory debugging to Docker build

Add debugging to see the current working directory and verify that lib directory
is properly copied and accessible for the tests.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: marshallswain

Dockerfile.node12

@@ -51,8 +51,8 @@ COPY --chown=node:node .eslintrc.js ./
 # Copy built files from builder stage
 COPY --from=builder /app/lib ./lib
 
-# Verify lib directory exists in runtime stage
-RUN ls -la lib/
+# Debug: Check current working directory and paths
+RUN pwd && ls -la && echo "Contents of lib:" && ls -la lib/
 
 # Fix mocha permissions
 RUN chmod +x node_modules/.bin/mocha