v0.47.15 — Gajae-Code (gjc) recorder support

Adds first-party support for Gajae-Code (gjc) — community contribution by @Yeachan-Heo (#4), reviewed and hardened before merge.

• New gjc adapter — tails Gajae-Code session JSONL (~/.gjc/agent/sessions/), no install. Record with --host gjc, or alongside the others with --host all. Same recorder, map, and efficiency score. (Experimental; minor next to Claude Code / OpenCode.)
• Review hardening: subagent transcripts are detected by the absence of a trailing session UUID (an underscored agent name no longer misfiles as a main run); subagent lanes fall back to the subagent type when no id is present; the redaction secret-assignment rule now also catches quoted JSON values ("password": "…").
• Cross-platform: separator-portable tests; verified green on ubuntu + windows-latest CI.
• README documents gjc as an optional experimental host in all four languages (en/ko/zh/ja).

Run it: npx @taewooopark/agent-blackbox@0.47.15 up --host gjc