The voice demo route handler imports @copilotkit/voice which was not
declared in these two package.json files. Other integrations either
had it or resolved it via hoisting, but mastra's Docker build failed.
The byoc-json-render demo imports @json-render/core, @json-render/react,
@radix-ui/react-checkbox, and @radix-ui/react-separator, but these were
never added to mastra's package.json (they exist in langgraph-python and
all other integrations). This causes webpack Module not found errors
during next build in Docker.
The showcase framework directories better reflect their role as
integration examples rather than distributable packages.
Renames showcase/packages/ -> showcase/integrations/ and updates
the test docker-compose file reference accordingly.
Tyler Slaton