refactor: update multi-agent rules to TMUX & refactor MAM skills scripts

- Update .agents/MULTI_AGENT_RULES.md & .ko.md to align with TMUX concepts
- Add .agents/INSTALL.md guide for MAM setup and workflows
- Clean up legacy markdown reports under .agents/reports/
- Refactor MAM scripts in .agents/skills/ (rename resolve_herdr_session to resolve_herdr_workspace)
- Improve workspace pane splitting/re-use logic in lib.sh
- Reduce paste safety sleep in send_keys_safe and support linking ~/.claude.json

.agents/skills/multi-agent-mux-stop/scripts/stop_session.sh

@@ -82,7 +82,7 @@ if [ "$PURGE" = "1" ]; then
   trap 'rm -f "$WORKSPACE_ROOT/.mam/purging-$SESSION_NAME"' EXIT
 fi
 
-HERDR_SERVER_NAME="$(resolve_herdr_session "$SESSION_NAME")"
+HERDR_SERVER_NAME="$(resolve_herdr_workspace "$SESSION_NAME")"
 export HERDR_SERVER_NAME
 
 # --agent 미지정 시 이름 suffix 로 fallback (P1-F)