v2.1.1 — CI Fix + Docs Reorganization

🔧 Bug Fixes

• CI restored: fixed 5 explicit any violations in open-sse/services/usage.ts (UsageQuota, JsonRecord, Error types)
• Draft releases cleaned: deleted all auto-generated duplicate draft releases (v2.0.17–v2.1.0)

📚 Documentation

• Root cleanup: moved 29 README.<lang>.md files from project root → docs/i18n/<lang>/README.md. Root now has only English README.md.
• i18n sync: all 11 docs/*.md files synced to 30 language folders (319 total updates) with language navigation bars.