feat: add production headless monitoring

[domcyrus]

Versioned JSONL and JSON snapshots for explicit non-interactive monitoring, stacked on #599 and related to #9.

• Fixes rate units, connection lifetime IDs, terminal status, output collisions, and bounded shutdown. JSONL is latest-value output; --json-log remains the separate connection-event stream.
• Incorporates refactor: split main.rs into bootstrap and tui, join workers on exit #598's thin-entry-point approach, with separate bootstrap, TUI, schema, writer, and orchestration modules. Documents the interface in English, Chinese, and Japanese.
• Uses the existing Windows dependency's console feature for shutdown signals. Verified: workspace tests, clippy, formatting, no-default-features check, release build, and dependency audit. Platform CI runs on this stacked base.