fix(reset): refuse every registration during a reset and purge only ids owned by the row's folder (#78)

Review round 2 (codex):
- R1: register_job reads .mam/reset-in-progress under the registry lock and
  refuses while a reset of the workspace owning <ws>/.mam/jobs is live, so the
  public registry.py register CLI and the API no longer bypass the gate. The
  reset's precheck takes that lock once after publishing its marker, so a
  registration is either seen by it or refused. The reset's own create passes
  MAM_RESET_OWNER_PID; the remote runner refuses the dispatch.
- R2: before each purge the reset re-runs stop's revalidate check
  (verify_session_uuid) for a post-discovered id against the row's folder and
  skips the target (id not verified) when it does not verify.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.agents/skills/multi-agent-mux-reset/SKILL.md

@@ -23,10 +23,10 @@ bash .agents/skills/multi-agent-mux-reset/scripts/reset.sh --yes [--dry-run]
 | Targets | Every registry row with `status: running` and `realpath(pane.cwd) == realpath(WS)`. Rows with any other status, worktree rows, and `orchestrator_uuids` are skipped and listed with their reason. |
 | Confirmation | `[y/N]` prompt; without a terminal `-y`/`--yes` is required (exits `3` otherwise). `--dry-run` inspects without `--yes` and changes nothing. |
 | Prechecks | Refuses before any change when an open job exists (prints the `registry.py ... close --request cancelled` command), when `.mam/loop-guard-active` or `.mam/update-in-progress` is held, when a target row lacks a valid agent or role, when a running `claude`/`grok` target has no recorded conversation id (the monitor had not pinned one; record it, or stop/purge it by hand first), when `.mam/reset-spec.json` is invalid, or when the caller itself is one of the targets. |
-| Lock & concurrency | Takes the update admission lock exclusively, acquires `.mam/loop-guard-active` and publishes `.mam/reset-in-progress`, then releases the admission lock and runs the prechecks. `run_loop.sh`, `update.sh` and another reset refuse on the loop marker; `multi-agent-mux-delegate-job submit` refuses on the reset marker. |
+| Lock & concurrency | Takes the update admission lock exclusively, acquires `.mam/loop-guard-active` and publishes `.mam/reset-in-progress`, then releases the admission lock and runs the prechecks. `run_loop.sh`, `update.sh` and another reset refuse on the loop marker; every job registration in this workspace's `.mam/jobs` (`multi-agent-mux-delegate-job submit`, `registry.py register`, the registry API) refuses on the reset marker, except the onboarding jobs of the reset's own `create_session.sh`. |
 | Spec file & rerun | Writes `.mam/reset-spec.json` atomically before the first stop/purge and removes it only when all targets reach `done`. Rerunning resumes from the spec file without re-purging already recreated agents (`created` or `done`). |
-| Sequence per target | Sequential (never parallel): ⓪ re-checks that its row still has the spec's agent and herdr server and that no job addressed to it is open, ① normal `stop_session.sh --reason reset` (a post-discovered agent's id is captured onto the row while herdr is live; `status: stopped`), ② checks that the row's id is the one recorded before the stop, ③ `stop_session.sh --reason reset --purge-conversation --yes` (using the row's recorded ID, never a CLI UUID), then `create_session.sh` with the original name, agent, role, `--herdr-session`, and `--herdr-workspace` (onboarding enabled by default). |
-| When skipped (exit 4) | The target is skipped and the reset continues to the next agent when step ⓪ finds a changed row (`row changed`) or an open job (`job open`) - nothing was changed for it -, or when step ② finds no id (`no conversation id recorded`) or an id other than the recorded one (`id not verified`), or step ③ exits `4` (`purge refused`, in-use gate) - it is stopped but resumable (its row keeps its id) and its conversation files are untouched. Rerun once the cause is gone, or resume it. |
+| Sequence per target | Sequential (never parallel): ⓪ re-checks that its row still has the spec's agent and herdr server and that no job addressed to it is open, ① normal `stop_session.sh --reason reset` (a post-discovered agent's id is captured onto the row while herdr is live; `status: stopped`), ② checks that the row's id is the one recorded before the stop and, for a post-discovered agent, that it still verifies as a conversation of the row's folder, ③ `stop_session.sh --reason reset --purge-conversation --yes` (using the row's recorded ID, never a CLI UUID), then `create_session.sh` with the original name, agent, role, `--herdr-session`, and `--herdr-workspace` (onboarding enabled by default). |
+| When skipped (exit 4) | The target is skipped and the reset continues to the next agent when step ⓪ finds a changed row (`row changed`) or an open job (`job open`) - nothing was changed for it -, or when step ② finds no id (`no conversation id recorded`) or an id other than the recorded one or one that does not verify for the row's folder (`id not verified`), or step ③ exits `4` (`purge refused`, in-use gate) - it is stopped but resumable (its row keeps its id) and its conversation files are untouched. Rerun once the cause is gone, or resume it. |
 
 | Exit | Meaning |
 |---|---|
@@ -44,5 +44,5 @@ bash .agents/skills/multi-agent-mux-reset/scripts/reset.sh --yes [--dry-run]
 - **No external process termination**: processes holding conversation files open (reported via `lsof` in `in_use_hints`) are never signalled by MAM; end them yourself when safe, then rerun.
 - **Shared stores preserved**: Grok's shared `memory-v2.db` is left intact during purge; only session rows and per-session files are removed.
 - **Orchestrator hook during reset**: while `.mam/loop-guard-active` is held by the reset, the AGY orchestrator's direct file-edit hook (`loop_delegation_guard.sh`) blocks direct edits until the reset finishes.
-- **Job submissions during a reset**: `multi-agent-mux-delegate-job submit` refuses with `a reset of <WS> is in progress` until the reset ends; submit again afterwards. A job registered for a target by other means after the precheck makes that target `job open` (skipped, not cancelled).
+- **Job submissions during a reset**: `multi-agent-mux-delegate-job submit` and `registry.py register` refuse with `a reset of <WS> is in progress` until the reset ends; submit again afterwards. A record written into `.mam/jobs` by hand for a target after the precheck makes that target `job open` (skipped, not cancelled) if it is there before that target's stop.
 - **Same-type post-discovered ordering**: when resetting multiple post-discovered agents of the same type, the second `create_session.sh` waits up to `MAM_ID_ORDER_WAIT_S` for the first agent's ID to be recorded; if it times out, rerun the reset once the ID is recorded.

.agents/skills/multi-agent-mux-reset/scripts/reset.sh

@@ -92,7 +92,9 @@ _refuse_locked() {
 # The update admission lock is taken exclusively, as update.sh does, while the
 # reset publishes its markers: a delegate submit admitted earlier has written
 # its job record (the precheck below sees it), and one admitted later sees
-# .mam/reset-in-progress and refuses.
+# .mam/reset-in-progress and refuses. Any other registration in .mam/jobs
+# (registry.py register, the delegation API) reads the marker under the
+# registry lock, which the precheck takes before it lists the open jobs.
 mkdir -p "$MAM"
 exec 7>>"$MAM/update-admission.lock"
 case "$("$PY" -m lib_py.pane_lock acquire --fd 7 --wait-env MAM_UPDATE_ADMISSION_WAIT_S)" in
@@ -255,6 +257,11 @@ for target_name in ${ENTRY_NAMES[@]+"${ENTRY_NAMES[@]}"}; do
         SKIPPED_ARGS+=(--skipped "$R_NAME:id_unverified")
         continue
       fi
+      if ! MAM_STATE_JSON="$STATE_JSON" "$PY" -m lib_py.reset id-owned --workspace "$WS" --session "$R_NAME"; then
+        echo "skipped $R_NAME: its recorded id $R_ROW_ID does not verify as a conversation of its folder, so it may be another folder's and nothing is purged; check it, purge it by hand if it is this agent's, and rerun the reset"
+        SKIPPED_ARGS+=(--skipped "$R_NAME:id_unverified")
+        continue
+      fi
 
       echo "reset [$R_NAME]: ${STOP_CMD[*]} --purge-conversation --yes"
       purge_rc=0
@@ -283,7 +290,8 @@ for target_name in ${ENTRY_NAMES[@]+"${ENTRY_NAMES[@]}"}; do
 
     echo "reset [$R_NAME]: ${CREATE_CMD[*]}"
     create_rc=0
-    "${CREATE_CMD[@]}" || create_rc=$?
+    # Its onboarding job is the one registration the reset marker lets through.
+    MAM_RESET_OWNER_PID="$$" "${CREATE_CMD[@]}" || create_rc=$?
     if [ "$create_rc" -ne 0 ]; then
       FAILED_SPEC="$R_NAME:create:$create_rc"
       break