fix(issue-50): the loop path waits by the registry on its pending record (review F1-F3)

F1: from phase two on, the loop's `_registry_wait` ran before the record was
reset to pending, so the waiter held a terminal record: the engine refused its
dispatch_wait_at merge and other waiters never saw it in the FIFO. The wait
(and the idle wait after it) now follows the `--status pending` update; s1
pins the order and u3c shows why a terminal self record cannot signal.
F2: the real-herdr box teardown survives a hung stop/delete, kills a server
bootstrapped by a late client call, and asserts the server and HOME are gone.
F3: the delegate-job SKILL.md exit 5 row names the registry wait.
Also drops the dead loop in s1.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

.agents/skills/multi-agent-mux-delegate-job/multi-agent-mux-delegate-job

@@ -518,7 +518,19 @@ EOF
         exit 5
       fi
 
-      # Registry wait (Issue #50), then idle wait
+      # Update job details in registry
+      "$PY" "$SCRIPT_DIR/scripts/registry.py" --registry-dir "$REGISTRY_DIR" update \
+          --job "$JOB_ID" \
+          --agent-session "$current_session" \
+          --prompt-file "$job_dir/prompt.md" \
+          --iteration "$iteration" \
+          --attempt-id "$attempt" \
+          --role "$display_role" \
+          --status "pending"
+
+      # Registry wait (Issue #50), then idle wait - on the record just reset to
+      # pending for this phase, so the waiter's signal is written and other
+      # waiters see this job in the FIFO (review F1)
       local cur_agent="$AGENT"
       [ "$_phase" = "reviewer" ] && cur_agent="$REVIEWER"
       if [ "$cur_agent" != "human" ] && ! _is_remote "$current_session"; then
@@ -534,16 +546,6 @@ EOF
         fi
       fi
 
-      # Update job details in registry
-      "$PY" "$SCRIPT_DIR/scripts/registry.py" --registry-dir "$REGISTRY_DIR" update \
-          --job "$JOB_ID" \
-          --agent-session "$current_session" \
-          --prompt-file "$job_dir/prompt.md" \
-          --iteration "$iteration" \
-          --attempt-id "$attempt" \
-          --role "$display_role" \
-          --status "pending"
-
       local _disp_tok=""
       _disp_tok="$("$PY" -c "import json, os; p=os.path.join('$REGISTRY_DIR', '$JOB_ID.json'); print(json.load(open(p)).get('dispatch_token','') or '') if os.path.exists(p) else print('')" 2>/dev/null || true)"