Add agenttrace

[luoyuctl]

Summary

• Add agenttrace to the Monitoring & Analytics section.
• Update both English and Simplified Chinese README entries.

Why

• agenttrace is a local TUI observability dashboard for AI coding agent sessions, including Claude Code-style logs, cost, token usage, latency, tool failures, anomalies, health, and diffs.

Checks

• README-only change; inspected the table diff locally.

[luoyuctl]

Refreshed the AgentTrace English and Chinese entries so they match the current local-first session-log observability positioning. Scope remains two README rows plus existing final-newline normalization.

Validation:

• git diff --check upstream/main...HEAD
• GitHub mergeability: CLEAN
• No repository checks are configured on this PR.