docs(stop): a purge removes the row; exit 4 covers a live agent (Issue #31)

The prose said a purge leaves a `terminated` row; the code removes it, and
the monitor never marks a stopped row. The step-5 list names what a claude
purge removes. The two code blocks (lines 52, 83) still say `terminated`:
changing them changes their inventory sha, which waits for approval.

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

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

@@ -62,7 +62,7 @@ bash .agents/skills/multi-agent-mux-stop/scripts/stop_session.sh \
 | 1 | From the checks before the stop, nothing was changed: YAML not found, or the session is not registered. **The registry update after the stop also exits 1** (the row disappeared from the YAML during the run) |
 | 2 | Bad arguments (including the retired `--mode` / `--capture-id` / `--graceful`), or `--agent` omitted and not resolvable |
 | 3 | `--purge-conversation` without `--yes` |
-| 4 | Purge aborted: the herdr session survived the kill chain |
+| 4 | Purge aborted: the herdr session, or an agent process still holding the conversation, survived the kill chain (nothing was changed) |
 | other | The registry update after the stop (YAML / DB write) failed and its code is passed through |
 
 Exits 2 and 3, and exit 1 from the pre-stop checks, come before anything is stopped, so nothing was changed. On exit 1 from the registry update, or an `other` exit, the session may already be down while its row still says `running`: check with `multi-agent-mux-status`, then run the stop again (it is idempotent).
@@ -86,14 +86,14 @@ stopped ──(stop default … again)───────────► stopp
 
 Fields written in STOP mode: `status: stopped`, `stopped_at`, `stopped_at_epoch`, `stop_reason`, `termination_mode: graceful`, `claude_session_id_own`/`agy_conversation_id_own` and `resumable: true`.
 
-If `--purge-conversation` is used: `status: terminated`, `terminated_at`, `terminated_at_epoch`, `termination_mode: purge` and `resumable: false`.
+If `--purge-conversation` is used: the row is removed from the YAML and the DB — no `terminated` row is left.
 
 The script:
 1. Verifies the session is in agent-sessions.yaml
 2. If `delegate_job_id` is set, automatically publishes a `progress --detail "terminating"` event to the multi-agent-mux-delegate-job registry
 3. Captures the `last_visible_status` from `herdr capture-pane` (so we have a final TUI snapshot for audit)
 4. Attempts graceful exit keys → SIGTERM kill-session → SIGKILL fallback
-5. For `purge-conversation`: deletes `~/.claude/projects/.../jsonl` (claude) or, for agy, `~/.gemini/antigravity-cli/conversations/<uuid>.db` with its `-wal`/`-shm`/`-journal` sidecars, `brain/<uuid>/`, `annotations/<uuid>.pbtxt` and `presence/<uuid>.lock` (the lock only once no live process references the conversation — Issue #10)
+5. For `purge-conversation`: deletes, for claude, every path the session owns — `projects/<key>/<uuid>.jsonl` and `<uuid>/`, `file-history/<uuid>/`, `session-env/<uuid>/`, `jobs/<uuid[:8]>/` (when its `state.json` names the session), stale `sessions/<pid>.json` (+ that pid's `.key`) and `<tmp>/claude-<uid>/*/<uuid>/`, then prints anything still carrying the UUID as `WARN residual:`; shared files such as `history.jsonl` are not rewritten (Issue #31). Or, for agy, `~/.gemini/antigravity-cli/conversations/<uuid>.db` with its `-wal`/`-shm`/`-journal` sidecars, `brain/<uuid>/`, `annotations/<uuid>.pbtxt` and `presence/<uuid>.lock` (the lock only once no live process references the conversation — Issue #10)
 6. Updates the YAML entry and SQLite database atomically
 7. If `delegate_job_id` is set, publishes a `completed` event to the multi-agent-mux-delegate-job registry
 
@@ -120,7 +120,7 @@ Exit codes: 0 removed, 1 stop/git failure, 2 not a worktree of the control root,
 - **Don't delete on-disk artifacts by default** — the agent's `*.jsonl` / `conversations/*.db` is the data that `multi-agent-mux-resume` needs. `--purge-conversation` is for when the user is genuinely done with the conversation and wants zero recovery chance.
 - **YAML is append-only until you write a stop** — if a previous run left the entry as `running` but herdr is actually dead (crash, host reboot), the YAML is stale. Running `multi-agent-mux-stop` will detect "herdr already dead, just update YAML" and proceed.
 - **Don't delete the `claude_session_id_own: null` placeholder** — when the user creates a fresh session with `multi-agent-mux-create` and never sent a message, the entry has `claude_session_id_own: null`. Stopping must preserve that field.
-- **Monitor skill may still be tracking** — if `multi-agent-mux-monitor` is running a heartbeat loop, stopping a session while it watches will trigger its `herdr ls != yaml` reconciliation. That's expected — let the monitor run, it will mark the entry as `terminated` on its own.
+- **Monitor skill may still be tracking** — if `multi-agent-mux-monitor` is running a heartbeat loop, stopping a session while it watches will trigger its `herdr ls != yaml` reconciliation. That's expected — let the monitor run: it leaves a `stopped` row as it is (drift A only marks a `running` row whose herdr is gone as `terminated`), and a purged row is gone.
 
 ## Verification
 

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

@@ -18,8 +18,8 @@
 #                              셋 다 실패하면 exit 2)
 #   --herdr-session <name>  — isolated herdr session name (alias: --herdr-server)
 #   --reason <reason>       — 상태 전이 사유 (stop_reason). 기본값 manual_stop
-#   --purge-conversation    — 디스크의 conversation artifact 까지 삭제.
+#   --purge-conversation    — 디스크의 conversation artifact 와 세션 부속 경로까지
-#                             status=terminated, resumable=false 로 전이하며
+#                             삭제하고 레지스트리 행(YAML+DB)을 지우며
 #                             resume 불가. --yes 없이는 확인 프롬프트(exit 3)
 #   --yes                   — --purge-conversation 의 확인 프롬프트 생략
 #
@@ -30,7 +30,7 @@
 # Exit codes:
 #   0 = success (or already-stopped no-op) | 1 = YAML not found / not registered
 #   2 = invalid args | 3 = interactive confirmation required (--yes 누락)
-#   4 = purge aborted (herdr session survived the kill chain)
+#   4 = purge aborted (herdr session or an agent process holding the conversation survived the kill chain)
 set -euo pipefail
 
 # shellcheck disable=SC1091
@@ -56,7 +56,7 @@ Arguments:
                              read from its registry row, not from where you stand.
   --reason <reason>    — stop_reason field (default: manual_stop)
   --purge-conversation — also delete on-disk conversation artifacts;
-                         status becomes terminated and resume is impossible
+                         the registry row is removed and resume is impossible
   --yes                — skip the --purge-conversation confirmation prompt
 EOF
 }