XERK-516 [Qwen K]: session migration + resume for qwen

.claude/rules/agent-archive.md

@@ -235,6 +235,10 @@ paths:
     (`qwen_session.QwenProjectionTail`) MIRRORS its bytes into the store, append-only, on its own
     cursor. A running qwen session is NOT un-excluded from the manifest (below) — qwen has no
     Trajectory viewer, so its native log is retention only and archives once the session ends.
+    Migration ([Qwen K], XERK-516) does NOT carry this `<tid>/qwen/` mirror: it is the display/metrics
+    feed, and qwen resumes from its OWN native log under `~/.qwen/projects/` (the file the bundle
+    carries under `.qwen-store/` instead). The target rebuilds this mirror from new events, exactly as
+    dsh's `<tid>/dsh/` feed is rebuilt. Keep the resumable log and this feed straight.
   - **A RUNNING dsh session is NOT excluded from the manifest** (`_running_slugs` subtracts
     `_live_dsh_slugs`), and that exception is what makes the Trajectory work at all. **A running
     QWEN session gets NO such carve-out** (XERK-512): qwen has a real ttyd TUI and no Trajectory

.claude/rules/qwen-migration.md

@@ -0,0 +1,60 @@
+---
+paths:
+  - "agent/hub-agent.py"
+  - "agent/tests/test_hub_agent.py"
+---
+
+# Qwen session migration + resume ([Qwen K], XERK-516)
+
+Split out of `.claude/rules/qwen.md` (which reached its size ceiling once every XERK-504 child had a
+section). This is the migration/resume child; read `qwen.md` for the qwen runtime around it
+(launcher [Qwen B], projection [Qwen S1], drive/liveness [Qwen C], archive [Qwen E]).
+
+XERK-101 (`CLAUDE.md`, "Migrating a session to another agent") extended to qwen — the dsh [K]
+(XERK-475, `.claude/rules/dsh.md`) analogue. The **load-bearing difference from dsh**: qwen is
+Claude-shaped, so its NATIVE LOG at `~/.qwen/projects/<slug>/chats/<id>.jsonl` *is* the durable store
+`qwen --resume <id>` reloads from — there is NO separate store like dsh's `DSH_SESSIONS_ROOT`, which
+is distinct from dsh's `<sid>/dsh/` display feed. So a qwen migration carries the native log itself.
+Full mechanics + rationale are in the `QWEN_STORE_ARCNAME` comment in `hub-agent.py`; the invariants
+a change must not undo:
+
+- **RESUME (process-death `--resume`, boot-adopt) was already wired by [Qwen B]/[Qwen C]; [K] only
+  PINS it.** `_launch_tmux(resume=True)` dispatches to `_launch_qwen(resume=True)` → `qwen --resume
+  <id>` at the transcript's origin cwd, and `_start_qwen_tail(resume=True)` restarts the projection
+  at the native log's EOF so it never re-projects/doubles the kept `<id>.jsonl` (the deterministic-
+  uuid projection is already there; qwen appends in place). Boot-adopt reattaches the tail the same
+  way. Never add a resume path that re-reads the native log from 0.
+- **MIGRATION carries the NATIVE LOG, not the projection feed.** `export_session` GLOB-locates it
+  (`_qwen_native_log`, `<id>.jsonl` across `QWEN_PROJECTS_ROOT/*/chats/`, the slug-rule-independent
+  discipline the tail/`_qwen_runtime_file` use) and packs it under the reserved `.qwen-store/chat.jsonl`
+  prefix (twin of dsh's `.dsh-store/`), truncated to its last complete line like the main transcript
+  (a live log is appended by its process). `_unpack_transcript` routes that member to a single target
+  FILE (`_qwen_store_dest`), **NEVER a dir** — the shared `chats/` dir holds every cwd-cohabiting
+  session's log, so it places exactly this session's `<id>.jsonl`. It is un-droppable resumable data,
+  so an oversized bundle is refused (like the dsh store) rather than shipped un-resumable.
+- **The `<slug>/<sid>/qwen/` raw-archive mirror ([Qwen E]) is the DISPLAY/metrics feed and is NEVER
+  carried by migration** — the target rebuilds it from new events past the log's EOF (the tail's
+  `_mirror_native` primes from the fresh mirror's size 0 and copies the whole placed native log).
+  Keep the two straight: resume reads the native log, not the mirror. This is the [K] correction the
+  ticket names.
+- **Cross-mount re-key is MANDATORY (upstream issue #2373: qwen keys the store on the working dir).**
+  The log lands under the TARGET cwd's slug — and qwen's slug rule is `_project_slug` (every
+  non-alnum→`-`, VERIFIED against real on-disk qwen project dirs; the G0 note's `/`→`-` was
+  imprecise), not a qwen-specific port. `_reconcile_qwen_store_cwd` then re-points the `cwd` carried
+  on EVERY native-log row (qwen has no single header line like dsh) from the source cwd (read from the
+  first row) to the localized worktree, so the placed log is self-consistent with where it now lives.
+  A no-op on a same-mount move (source cwd == target); never raises the migration over a store detail.
+- **A qwen session migrated to a host without qwen falls back to CLAUDE cleanly** — the existing
+  `agent_type_configured` rebuild guard in `_resume_at_cwd` (per-runtime, not dsh-only). `want_qwen`
+  (`agentType=="qwen" and qwen_configured()`) gates the unpack, so a claude-fallback import DROPS the
+  `.qwen-store/` member (no resume to feed it), exactly as a stray dsh store is dropped.
+- **Model/endpoint re-validation is against the TARGET host's config on every launch.** `_launch_qwen`
+  reads the TARGET's `QWEN_MODEL_BASE_URL`/`QWEN_MODEL_API_KEY_ENV` (never the source's) and keeps a
+  carried `model` only if it passes `QWEN_IDENT_RE`, else the host default. qwen has NO model-list
+  discovery (unlike local-model failover), so an id the target's endpoint does not actually serve is
+  caught at `_confirm_qwen_launch` (clean teardown + a reason via `_refuse_start`), not pre-validated.
+- Tests: the qwen cases in `TestMigrateSession` (`test_a_qwen_bundle_carries_the_native_log_*`,
+  `test_a_claude_import_drops_a_stray_qwen_log`, `test_import_places_and_rekeys_the_qwen_log_cross_mount`,
+  `test_import_drops_the_qwen_log_when_target_lacks_qwen`, `test_qwen_store_dest_uses_the_project_slug_rule`,
+  `test_reconcile_qwen_log_cwd_is_a_noop_on_same_mount`). A real cross-host move actually resumed by
+  qwen is host-proof only — qwen is not installed in CI — the footing [Qwen C]/[Qwen E] shipped on.

.claude/rules/qwen.md

@@ -461,3 +461,12 @@ ticket-branch directive — no new launch code). The mechanics — the `/runtime
 gate, the per-runtime `findTicketHost` capability filter, the board `qwenAvailable`/picker, and the
 Android parity — live in **`.claude/rules/turma-board.md`**'s Runtime-row section (board-scoped,
 where the dsh [I] board detail's twin belongs), whose `paths:` load for the board files this touched.
+
+## [Qwen K] (XERK-516) shipped: session migration + resume
+
+Session migration + resume for a qwen session (the dsh [K] analogue) lives in
+**`.claude/rules/qwen-migration.md`** — split out to keep this file under its size ceiling; its
+`paths:` include `hub-agent.py`, so it co-loads with this file when the migration code is touched.
+The load-bearing point: qwen is Claude-shaped, so its NATIVE LOG *is* the store `qwen --resume`
+reloads from (no separate store like dsh's `DSH_SESSIONS_ROOT`) — a migration carries that log under
+`.qwen-store/`, places it at the target cwd's slug and re-keys its per-row `cwd`.

CLAUDE.md

@@ -36,6 +36,7 @@ that component's files.
 | `.claude/rules/routing-eval.md` | `bench/archive/**`, the routing docs | archive-sourced replay eval: the requestId turn unit, curation gates, why routing is per-session |
 | `.claude/rules/dsh.md` | `poc/turma-2.0-poc/**`, `agent/**` | dsh ADR + per-child mechanics (XERK-460) |
 | `.claude/rules/qwen.md` | `agent/hub-agent.py`, `turma/server.js`, `sessions.html`, `android/**` | Qwen Code runtime plumbing (XERK-504) |
+| `.claude/rules/qwen-migration.md` | `agent/hub-agent.py` | qwen session migration + resume (XERK-516 [Qwen K]): the native log as the resumable store |
 | `.claude/rules/dsh-input.md` | `agent/dsh_session.py` | driving a dsh session (XERK-467 [C]): socket, driver, input |
 | `.claude/rules/dsh-delegation.md` | `agent/dsh_transcript.py` | dsh delegation (XERK-474 [J]): bg-agent/workflow rows + `subagentHistory` |
 | `.claude/rules/dsh-guard.md` | `agent/dsh/guard/**` | dsh safety guard (XERK-470 [F]): deny policy on dsh's pipeline |