fix(session): handle missing and historical logs on deletion

[wangxiaocuo]

Fixes #584

Problem

When a session's JSONL log has already been removed but its Workspace entry remains, the permanent-delete RPC calls readSessionState first and fails with session/not-found. The stale sidebar entry cannot be cleared. The JSONL deletion path also removes only the selected current generation, leaving older generation files behind.

Changes

• Resolve a session from its attached/live header or sessionPersistence.stat, without reading the full event log. Clear stale Workspace metadata and emit removal even when the durable log is absent; return { deleted: false } for that case.
• Keep subagent and busy-agent guards. Report storage errors, and do not delete an unreadable artifact when no valid header can be identified.
• Delete every recognized JSONL generation for the selected session while holding its write claim and directory lease. Other sessions and Workspace files remain untouched.
• Cover Host command behavior, real JSONL persistence, retry after a storage failure, and Harness RPC deletion, including repeated deletion.

Patch scope

This updates the existing patch-package patches for @deepseek-ai/dsh-api-session-controller@0.2.0-rc.2 and @deepseek-ai/dsh-session-persistence-jsonl@0.2.0-rc.2. The required delete behavior is inside Harness and has no public extension point; it serves Desktop's existing session/delete RPC. No UI slot or plugin contract changes. These patch changes can be removed when the upstream Harness packages provide equivalent behavior.

Verification

• npm ci (all patches reapplied from a clean install)
• npm test (182 files, 1,619 tests, including a real macOS Harness subprocess)
• npm run typecheck
• npm run build
• git diff --check

Windows and the reporter's actual Profile/installed-app UI have not been tested.