Add translation adapter interface for self-hosted backends

[louzt]

Summary

This PR introduces a translation adapter boundary plus a LibreTranslate-oriented adapter path.

It is intentionally separate from the browser-native PR so the self-hosted / backend-driven path can be evaluated independently from the local Translator API experiment.

What this does

• introduces a swappable translation adapter interface
• adds an initial self-hosted backend-oriented translation path
• keeps the translation backend behind an adapter seam instead of coupling the client to one concrete service shape

What this does not do

• no claim that this alone implements issue Automatic language translation #101 as an IRC-side/server-side feature
• no requirement that ObsidianIRC ship with a hosted translation service
• no attempt to replace the browser-native progressive-enhancement path in Feat: Browser-native message translation (distinct from UI localization) #173

How this relates to the other open translation work

• feat/i18n #171 = UI localization / dictionaries
• Feat: Browser-native message translation (distinct from UI localization) #173 = browser-native per-message translation using the Translator API as optional progressive enhancement
• Add translation adapter interface for self-hosted backends #174 = backend / self-hosted adapter seam
• fix: harden IRCv3 tag parsing and multiline protocol helpers #175 = IRCv3 helper/protocol hardening useful for translation-adjacent follow-up work

The intent is to keep these reviewable independently:

• Feat: Browser-native message translation (distinct from UI localization) #173 proves the client-side interaction model without a backend dependency
• Add translation adapter interface for self-hosted backends #174 provides a path for maintainers who prefer self-hosted backends such as LibreTranslate-style deployments
• fix: harden IRCv3 tag parsing and multiline protocol helpers #175 keeps generic protocol/helper correctness separate from product-scope translation review

Deployment follow-up

For maintainers who want an operational next-step note for a self-hosted deployment, I wrote a separate follow-up here:

• Self-hosted translation follow-up (LibreTranslate / proxy / Docker): https://gist.github.com/louzt/d12a4fa925446630290c0e1171ea6131

That note is intentionally about deployment and reverse-proxy/service layout. It should be read as follow-up guidance for the self-hosted path, not as proof that this PR already provides an IRC-side network translation layer.

[coderabbitai]

Warning

Rate limit exceeded

@louzt has exceeded the limit for the number of commits that can be reviewed per hour. Please wait 56 minutes and 51 seconds before requesting another review.

Your organization is not enrolled in usage-based pricing. Contact your admin to enable usage-based pricing to continue reviews beyond the rate limit, or try again in 56 minutes and 51 seconds.

⌛ How to resolve this issue?

After the wait time has elapsed, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

We recommend that you space out your commits to avoid hitting the rate limit.

🚦 How do rate limits work?

CodeRabbit enforces hourly rate limits for each developer per organization.

Our paid plans have higher rate limits than the trial, open-source and free plans. In all cases, we re-allow further reviews after a brief timeout.

Please see our FAQ for further information.

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 1052fd35-1cc9-4fb2-ab86-78123f76aa68

📥 Commits

Reviewing files that changed from the base of the PR and between e731866 and 4b14222.

📒 Files selected for processing (3)

• src/lib/translation/adapters.ts
• src/lib/translation/index.ts
• tests/lib/libreTranslateAdapter.test.ts

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}