Top-level App component

- [ ] Create a top-level wrapper component with configuration options.
- [ ] Use passed arguments for configuration to replace defaults in components etc.
- [ ] Add templating arguments.
- [ ] Use Context API to handle state if possible.

No files, tests, or entry points are named. Start by surveying the existing React component structure and how components receive configuration and state; determine how the proposed top-level wrapper, configuration and templating arguments, and Context API fit together. Done means the checklist requirements are implemented consistently across the component library and verified by the project’s existing checks.

Written by the indexing model from the issue text.