Add i18n support across web, panel, and bot replies

[Jamesllllllllll]

Summary

Add the shipped i18n work across the website, Twitch panel, and bot replies, and cut it as patch release 0.3.1.

What Changed

• added localized resources and runtime wiring for the website, Twitch panel, and bot reply namespaces
• added owner-controlled channel bot language settings, with English remaining the default until the owner explicitly changes it
• localized more support-event and StreamElements bot replies, plus shared VIP-token automation copy and translation-help UI
• added panel locale resolution/persistence coverage and fixed the website language picker regressions so locale changes apply immediately without flashing back
• updated the changelog and README summary for the patch release

How To Test

1. Run npm run lint
2. Run npm run check:generated
3. Run npm run check:i18n
4. Run npm run check:prepush

Screenshots Or UI Notes

Visible UI changes include the website language picker behavior, the non-English translation feedback CTA, the dashboard bot-language selector, and the localized Twitch panel picker/content.

Checklist

• I tested the change locally
• I updated docs or examples if needed
• I called out any follow-up work or known limitations

[github-actions]

Preview deployment updated.

App: https://request-bot-pr-68.jameskeezer.workers.dev
Frontend worker: request-bot-pr-68
Backend worker: request-bot-backend-pr-68