Add growth assets and npm launch docs

[luoyuctl]

Summary

• Reposition README/Chinese README around local cost, token, time, and slow-run diagnosis jobs
• Add comparison and roadmap docs tied to the current growth issues
• Update npm package metadata/readme and site links for the npm launch path

Validation

• git diff --check
• go test ./...
• node package/json + npm install/run syntax checks
• npm pack --dry-run
• go build + npm wrapper --version
• scripts/ci/check-docs-commands.sh
• scripts/ci/check-pages-artifact.sh site

npm publish status

• npm registry currently returns 404 for agenttrace, so the package name appears unpublished
• npm install script found the v0.4.0 GitHub release asset but the download failed with a socket hang up in local validation
• publish was not executed because this session has no npm auth after context compaction and the token is not recoverable from available context