fix(issue-10,11,13,15): complete agy purge, orchestrator purge, workspace-anchored registry

Issue #10 - agy purge_artifacts left resumable pieces behind: it now also
removes the SQLite sidecars (-wal/-shm/-journal), the title annotation and
the presence lock (the lock only once no live process references the
conversation), and residual_artifacts() reports anything under
~/.gemini/antigravity-cli still carrying the uuid.

Issue #13 - the orchestrator has no herdr_sessions row, so its conversation
could not be purged by any skill. `lib_py.agents purge <agent|auto> <uuid>`
resolves the adapter from what is on disk (orchestrator_uuids stores bare
uuids), refuses while a live process names the uuid (conversation_in_use:
process list minus the caller's own lineage, plus lsof), and prints what it
purged. `orc_onboard.sh --remove <uuid> --purge-conversation --yes [--agent]`
runs it before the registry update so a refusal changes nothing (exit 4
without --yes, 5 while in use).

Issue #11 - "Successfully removeed": conjugate add/remove explicitly.

Issue #15 - the job registry and audit log followed the caller's cwd, so the
pytest suite (create_session.sh with its default onboarding job, run from the
repo root) had left 593 test records in the real .mam/jobs. Defaults now
resolve MAM_JOBS_DIR / DELEGATE_JOB_LOGS_DIR, then $WORKSPACE_ROOT/.mam/...,
then the cwd (mqtt_common.default_registry_dir / get_logs_dir; registry.py,
publish_event.py, service.py, create_session.sh, stop_session.sh); the
sandbox fixture pins both. The tier suites that used to leak now leave the
real registry untouched (881 records before and after).

Tests: test_issue10_13_purge.py (13), test_issue15_registry_isolation.py (7);
T-O13 pins the corrected message; the R1 helper test and B-9 logs-dir test
now assert the workspace-anchored contract; publish_event snapshot updated.

Refs #10 #11 #13 #15

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VCgu9Fa9iT7TbJUSzdq4Ff

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

@@ -105,7 +105,7 @@ The script:
 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 `~/.gemini/antigravity-cli/conversations/...db` + `brain/...` (agy)
+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)
 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