chore(release): prepare v2.0.1

[ryan-wong-coder]

Summary

• publish the v2.0.1 compatibility, security, and online key-lifecycle notes
• pin README, SDK, container, release workflow, and six-language website onboarding to v2.0.1
• add a routed official-site operations guide and a complete Chinese repository runbook

Compatibility

• no V2 wire, proofstore v5, WAL, .sproof v2, or .tdbackup v5 format change
• immediate registry mutation remains a single-process guarantee; multi-replica deployments require ordered authenticated event distribution

Local validation

• go mod verify
• release verify-policy
• go test -mod=readonly ./... -count=1
• go test -race -mod=readonly ./...
• go vet ./...
• govulncheck v1.6.0 ./...
• Admin Web: build, 26 unit tests, 4 Playwright E2E
• desktop frontend build
• official website build and release-first guide policy
• npm audit --audit-level=high for all three frontend dependency graphs
• Chrome desktop/mobile and six-locale navigation QA
• native darwin/arm64 v2.0.1 release archive build

Closes #623