chore: remove misleading Node 10 TODO comments - #2592

Summary

• Replace TODO comment in appWorker.ts (WORKER_BOOTSTRAP string) with an explanation
  that the polyfill is required because the code runs in the user's RN environment where
  import/require are unavailable.
• Replace TODO comment in forkedAppWorker.ts with an explanation that the simple
  file:// string concatenation is intentionally kept to avoid URL encoding side-effects
  from url.pathToFileURL().

Files changed

• src/debugger/appWorker.ts
• src/debugger/forkedAppWorker.ts

Plan de test

• Run gulp build — no errors
• Verify no functional behavior changed (comments only)

Closes #2607