Replace placeholder failing test scripts

[vishxrad]

Summary

Some test scripts are placeholders that intentionally fail with Error: no test specified. This is confusing for contributors because running the expected test command reports a failure even when nothing is wrong.

Current behavior

These commands fail by design:

pnpm test
pnpm --filter @openuidev/react-ui test

Relevant files:

• package.json
• packages/react-ui/package.json

Suggested implementation

Replace the placeholder scripts with useful behavior. Possible approaches:

• make the root test script run tests for packages that actually have tests
• add a small real smoke/unit test setup for @openuidev/react-ui
• or remove/rename placeholder scripts so contributors are not guided toward failing commands

Acceptance criteria

• Running the documented/default test command no longer fails solely because of a placeholder script.
• The chosen behavior is documented in package scripts and is consistent with the monorepo workflow.
• Existing package-level test scripts that already pass keep working.