feat(cli,registry): introduce --herdr-workspace option and decouple socket fallback chains

.agents/skills/multi-agent-mux-create/scripts/create_session.sh

@@ -37,6 +37,10 @@ Options:
   --dry-run           print commands without executing
   --herdr-session NAME specify isolated herdr session name (alias: --herdr-server)
   --herdr-server NAME  specify isolated herdr session name (legacy alias)
+  --herdr-workspace NAME workspace label recorded in the registry
+                          (flag > \$HERDR_WORKSPACE > workspace slug without mam-).
+                          A label only — it never selects a herdr socket;
+                          use --herdr-session for that.
   --submit-job PROMPT submit a job to multi-agent-mux-delegate-job registry with the given prompt
   --onboard           automatically submit a project alignment/orientation job to the new agent
   --no-onboard        disable automatic onboarding job submission
@@ -53,6 +57,7 @@ SESSION_NAME=""
 USE_WRAPPER=0
 DRY_RUN=0
 HERDR_SERVER_OPT=""
+HERDR_WORKSPACE_OPT=""
 SUBMIT_JOB_PROMPT=""
 ONBOARD=1
 
@@ -65,6 +70,7 @@ while [ $# -gt 0 ]; do
     --wrapper)   USE_WRAPPER=1; shift ;;
     --dry-run)   DRY_RUN=1; shift ;;
     --herdr-session|--herdr-server) HERDR_SERVER_OPT="$2"; shift 2 ;;
+    --herdr-workspace) HERDR_WORKSPACE_OPT="$2"; shift 2 ;;
     --submit-job) SUBMIT_JOB_PROMPT="$2"; shift 2 ;;
     --onboard)   ONBOARD=1; shift ;;
     --no-onboard) ONBOARD=0; shift ;;
@@ -137,6 +143,10 @@ LOCAL_BIN="${LOCAL_BIN:-$HOME/.local/bin}"
 WRAPPER="$LOCAL_BIN/$SESSION_NAME"
 
 ws_slug="$(derive_workspace_slug "$WORKSPACE")"
+# 플래그 > 환경변수 > 워크스페이스 슬러그 (C-3: HERDR_SESSION_NAME 과 대칭).
+# D5: resolve_herdr_workspace 를 쓰지 않는다 — 동명 terminated 행 위에 재생성할 때
+#     낡은 pane.cwd 에서 파생된 라벨을 물려받기 때문 (create 는 사실을 세우는 쪽).
+MAM_WS_LABEL="${HERDR_WORKSPACE_OPT:-${HERDR_WORKSPACE:-${ws_slug#mam-}}}"
 if [ -z "$HERDR_SERVER_OPT" ]; then
   if [ -z "${HERDR_SESSION_NAME:-}" ] || [ "$HERDR_SESSION_NAME" = "default" ]; then
     export HERDR_SESSION_NAME="$ws_slug"
@@ -197,7 +207,7 @@ spawn() {
 }
 
 if [ "$DRY_RUN" = "1" ]; then
-  echo "[dry-run] would spawn: herdr session '$SESSION_NAME' in $WORKSPACE (agent=$AGENT, herdr_session=${HERDR_SESSION_NAME:-default})"
+  echo "[dry-run] would spawn: herdr session '$SESSION_NAME' in $WORKSPACE (agent=$AGENT, herdr_session=${HERDR_SESSION_NAME:-default}, herdr_workspace=${MAM_WS_LABEL})"
   exit 0
 fi
 
@@ -214,7 +224,7 @@ cleanup_herdr_on_error() {
 trap cleanup_herdr_on_error EXIT
 
 if [ -z "$HERDR_SERVER_OPT" ]; then
-  RESOLVED_SERVER="$(resolve_herdr_workspace "$SESSION_NAME" "$WORKSPACE")"
+  RESOLVED_SERVER="$(resolve_herdr_session "$SESSION_NAME" "$WORKSPACE")"
   export HERDR_SESSION_NAME="${HERDR_SESSION_NAME:-$RESOLVED_SERVER}"
 fi
 
@@ -285,6 +295,7 @@ atomic_dump_yaml "$AGENT_SESSIONS_YAML" \
   HERDR_EPOCH="$HERDR_EPOCH" PANE_PID="$PANE_PID" PANE_CWD="$PANE_CWD" \
   CMD_FULL="$CMD_FULL" START_CMD="$START_CMD" CHILD_PID="$CHILD_PID" \
   HERDR_SESSION_NAME="${HERDR_SESSION_NAME:-default}" \
+  MAM_WS_LABEL="$MAM_WS_LABEL" \
   SESSION_UUID="$SESSION_UUID" \
   DELEGATE_JOB_ID="$DELEGATE_JOB_ID" ROLE="$ROLE" <<'PYEOF'
 name = os.environ['SESSION_NAME']
@@ -313,6 +324,7 @@ entry = {
     'herdr_session_epoch': int(epoch) if epoch.isdigit() else 0,
     'herdr_session': server_name,
     'herdr_server': server_name,
+    'herdr_workspace': os.environ.get('MAM_WS_LABEL', ''),
     'delegate_job_id': os.environ.get('DELEGATE_JOB_ID', '') or None,
     'pane': {
         'index': 0,