fix(core): Preserve ownership during session cleanup

docs/developers/qwen-serve-protocol.md

@@ -2481,7 +2481,9 @@ Response:
 }
 ```
 
-`resolveConflicts` is optional and defaults to `false`. By default, active and archived files with the same id are reported in `errors`, and neither copy is moved, removed, or overwritten. Archiving a live session still performs the strict close described above before classifying the conflict, so that close may flush queued records to the active transcript. With `resolveConflicts: true`, archive keeps the archived copy, removes the active copy, and reports the id in both `archived` and `resolvedConflicts`. `errors` entries have `{ "sessionId": "<uuid>", "error": "message" }`.
+`resolveConflicts` is optional and defaults to `false`. By default, active and archived files with the same id are reported in `errors`, and neither copy is moved, removed, or overwritten. Archiving a live session still performs the strict close described above before classifying the conflict, so that close may flush queued records to the active transcript. With `resolveConflicts: true`, archive repairs the conflict only when both copies are regular transcript files that the selected workspace may maintain, including owned empty or damaged transcripts. It keeps the archived copy, removes the active copy, and reports the id in both `archived` and `resolvedConflicts`. The option does not bypass ownership checks; mixed local/foreign or otherwise ambiguous ownership is reported in `errors`, and neither copy is moved. `errors` entries have `{ "sessionId": "<uuid>", "error": "message" }`.
+
+The transcript move or conflict repair is not rolled back if a later cleanup ownership check fails. In that case the id may appear only in `errors`, even though the archive state already changed, and may be omitted from `archived` and `resolvedConflicts`. Before treating such an error as proof that the active copy or conflict remains, re-read the session list for the same workspace and use its authoritative archive state.
 
 Lifecycle conflicts are batch item outcomes: the workspace-less and workspace-qualified routes return HTTP `200` with the conflict in `errors`. This replaces the earlier workspace-qualified HTTP `409 session_conflict` envelope; clients that called that route must inspect the batch response. Internal-runtime REST batches preserve the safe conflict message while continuing to redact other per-session failure details.
 
@@ -2507,7 +2509,9 @@ Response:
 }
 ```
 
-`resolveConflicts` is optional and defaults to `false`. By default, simultaneous active and archived JSONL files produce a conflict in `errors`, and neither copy is moved, removed, or overwritten; an active-only session is returned in `alreadyActive`. With `resolveConflicts: true`, unarchive keeps the active copy, removes the archived copy, and reports the id in both `unarchived` and `resolvedConflicts`. Archive or unarchive in flight for the same id returns `409 session_archiving` before starting the batch.
+`resolveConflicts` is optional and defaults to `false`. By default, simultaneous active and archived JSONL files produce a conflict in `errors`, and neither copy is moved, removed, or overwritten; an active-only session is returned in `alreadyActive`. With `resolveConflicts: true`, unarchive repairs the conflict only when both copies are regular transcript files that the selected workspace may maintain, including owned empty or damaged transcripts. It keeps the active copy, removes the archived copy, and reports the id in both `unarchived` and `resolvedConflicts`. The option does not bypass ownership checks; mixed local/foreign or otherwise ambiguous ownership is reported in `errors`, and neither copy is moved. Archive or unarchive in flight for the same id returns `409 session_archiving` before starting the batch.
+
+The transcript move or conflict repair is not rolled back if a later cleanup ownership check fails. In that case the id may appear only in `errors`, even though the archive state already changed, and may be omitted from `unarchived` and `resolvedConflicts`. Before treating such an error as proof that the archived copy or conflict remains, re-read the session list for the same workspace and use its authoritative archive state.
 
 ACP-over-HTTP uses the same request and response bodies through vendor methods `_qwen/sessions/archive` and `_qwen/sessions/unarchive`. The REST route table maps `POST /sessions/archive` and `POST /sessions/unarchive` to those methods for ACP transports.