Localize ask decision UI

[jerryfan]

I found one small UX issue: ask_user is a decision point where users choose answers, add notes, elaborate, submit, or cancel. If those labels are misread, the agent can continue with the wrong direction.

This PR makes that decision surface optionally localizable while preserving the current English strings as fallbacks.

• No new dependency
• No behavior change without an i18n provider
• English remains the default/fallback
• Locales: es, fr, pt-BR — Western default per broad developer/HITL workflow fit
• Covers tool label/description, prompt snippet, submit actions, custom answer label, review text, placeholders, and result labels

Validation:

• npm install --ignore-scripts
• npx tsc --noEmit
• npm pack --dry-run

Note: npm test is currently blocked locally on Node 20/Windows because node --test cannot load .ts test files directly and the package script passes tests/*.test.ts without a loader. I left that environment issue out of the implementation path.

[eko24ive]

Thanks for the PR. I'll dive into it tomorrow, cause I was working on the same thing in parallel, so I'll have to check how it can be "synced"