Enhance copilot-instructions.md to include web-app instructions #1502
Description
Enhance the copilot-instructions.md to include more strict and guided instructions
ex:
- Use React functional components only.
- Follow MUI v5 conventions.
- Prefer `<Box>` for layout instead of `<div>`.
- Use theme tokens (`theme.palette.*`, `theme.spacing`, etc.).
- Keep components < 150 lines; extract subcomponents as needed.
As we have a monorepo, set up these instructions in a mindful organized manner to not conflict with the api code