Stand up managed translation platform (Crowdin or Weblate)

[kwsantiago]

Problem

#230 seeded four locales (de, es, ja, pt-BR) and established CI drift enforcement, but the translator workflow is still PR-based. Community translators without a GitHub account or PR workflow familiarity cannot contribute.

Proposal

Stand up a managed translation platform once translator volume justifies the setup cost. Two options:

Crowdin (matches Amber)

• Pros: instant signup, free for OSS (requires OSS plan application), drop-in GitHub Action, Amber's config is a copyable template
• Cons: proprietary SaaS
• Setup: create project, add CROWDIN_PROJECT_ID + CROWDIN_PERSONAL_TOKEN secrets, add crowdin.yml and .github/workflows/crowdin.yml, upload seeded translations so translators start at 100% coverage

Weblate (libre hosting)

• Pros: free libre hosting at hosted.weblate.org, no repo secrets needed (they pull via deploy key), open source platform used by F-Droid and Tor Browser
• Cons: application for libre hosting takes days to weeks
• Setup: apply for libre plan, add deploy key / webhook, configure Android resource format

Acceptance

• Platform chosen, project created, seed translations uploaded
• Sync workflow wired (PR-opening on their side or ours)
• README link updated: replace the "on the backlog" note in the Contributing section with the project URL
• CONTRIBUTING.md translator workflow section updated to point at the platform

References

• Amber's crowdin.yml and workflow
• Weblate libre hosting