feat: optimize react testing runtime and add prettier

[Lojhan]

Summary

• optimize react testing integration with batched IPC metrics and safer cleanup
• replace proxy hot paths with static bindings for screen/fireEvent
• move runtime config from env mutation to argv parsing/injection
• add benchmark harness and cross-runner benchmark fixtures
• add Prettier with @ianvs/prettier-plugin-sort-imports and format scripts

Validation

• npm run typecheck
• POKU_REACT_TEST_DOM=happy-dom node --import=tsx ./node_modules/poku/lib/bin/index.js tests --showLogs
• POKU_REACT_TEST_DOM=jsdom node --import=tsx ./node_modules/poku/lib/bin/index.js tests --showLogs