feat(web): Sync the AgentX snapshot and sanitize internal credentials

[Hang-Hu]

Summary

• Sync the current AgentX source snapshot into web without carrying source Git history.
• Replace internal credentials, private network endpoints, signed fixture URLs, and callable ModelScope MCP endpoints with example values.
• Preserve the 12 intended public demo share URLs.
• Exclude local .env and generated build/dependency outputs from the commit.

Verification

• pnpm install --frozen-lockfile
• NODE_OPTIONS=--localstorage-file=/private/tmp/langcrew-agentx-vitest-localstorage.json pnpm test --run: 331/331 passed
• pnpm build: passed
• Gitleaks staged scan: no leaks found
• Full directory Gitleaks scan only reports the existing generic-api-key false positive in public/NZsdk.min.2.8.1.js; the matching minified SDK file is unchanged by this PR.

Notes

• This is one snapshot commit based on AgentX source commit 2bacbf6.
• No source repository Git history is included.