fix(cloud-agent-next): release unadmitted queued messages on quarantine

[eshurakov]

Summary

• When a runtime is quarantined, keep queued messages that never reached a committed attach or prompt.
• Clear wrapperInstanceId so the replacement runtime can pick them up through the normal queue drain.
• Still fail accepted work, committed attach proofs, prompt operations, unresolved dispatch, and exhausted attach failures.

Stack

Remaining control-plane recovery stack. #5912–#5918 are merged. Merge from the bottom.

1. fix(cloud-agent-next): control-plane recovery follow-ups #5919 eshurakov/recovery-stack → main
2. fix(cloud-agent-next): release unadmitted queued messages on quarantine #5920 eshurakov/recovery-not-ready-retry → eshurakov/recovery-stack
3. fix(cloud-agent-next): recover cold attach after idle stop #5957 eshurakov/recovery-cold-bootstrap-attach → eshurakov/recovery-not-ready-retry
4. fix(web): keep Cloud Agent workspace tabs stable during progress #5958 eshurakov/ca-stable-workspace-tabs → eshurakov/recovery-cold-bootstrap-attach

Reviewer Notes

One commit. Unique vs parent.

Live local E2E did not prove replacement completion: killing only the primary left the proxy up, so pendingRuntimeCleanup blocked later dispatch until preparation_timeout. That stop-lifecycle gap is out of scope here. This PR covers the original kilo_unhealthy unadmitted-queue incident path.

[kilo-code-bot]

Code Review Summary

Status: No Issues Found | Recommendation: Merge

Executive Summary

Quarantine release still drops leftover attach proofs so replacement drain can retry unadmitted messages; no remaining issues on current HEAD.

Files Reviewed (3 files)

• services/cloud-agent-next/src/sandbox-session/SandboxSession.ts
• services/cloud-agent-next/src/sandbox-session/recovery/quarantine-releases-unadmitted-queue.test.ts
• services/cloud-agent-next/src/sandbox-session/session-message-queue.ts

Previous Review Summaries (6 snapshots, latest commit d331d9e)

Current summary above is authoritative. Previous snapshots are kept for context only.

Previous review (commit d331d9e)

Status: No Issues Found | Recommendation: Merge

Executive Summary

Quarantine release drops leftover attach proofs so replacement drain can retry unadmitted messages; no remaining issues on current HEAD.

Files Reviewed (3 files)

• services/cloud-agent-next/src/sandbox-session/SandboxSession.ts
• services/cloud-agent-next/src/sandbox-session/recovery/quarantine-releases-unadmitted-queue.test.ts
• services/cloud-agent-next/src/sandbox-session/session-message-queue.ts

Previous review (commit ee70bfe)

Status: No Issues Found | Recommendation: Merge

Executive Summary

Incremental change only removes the control-plane retry plan doc; no remaining issues on current HEAD.

Files Reviewed (1 files)

• docs/plans/control-plane-not-ready-retry.md

Previous review (commit 95fbae6)

Status: No Issues Found | Recommendation: Merge

Executive Summary

Quarantine release drops leftover attach proofs so replacement drain can retry unadmitted messages; no remaining issues on current HEAD.

Files Reviewed (4 files)

• docs/plans/control-plane-not-ready-retry.md
• services/cloud-agent-next/src/sandbox-session/SandboxSession.ts
• services/cloud-agent-next/src/sandbox-session/recovery/quarantine-releases-unadmitted-queue.test.ts
• services/cloud-agent-next/src/sandbox-session/session-message-queue.ts

Previous review (commit 5770e3f)

Status: No Issues Found | Recommendation: Merge

Executive Summary

Quarantine release drops leftover attach proofs so replacement drain can retry unadmitted messages; no remaining issues on current HEAD.

Files Reviewed (4 files)

• docs/plans/control-plane-not-ready-retry.md
• services/cloud-agent-next/src/sandbox-session/SandboxSession.ts
• services/cloud-agent-next/src/sandbox-session/recovery/quarantine-releases-unadmitted-queue.test.ts
• services/cloud-agent-next/src/sandbox-session/session-message-queue.ts

Previous review (commit 14244c1)

Status: No Issues Found | Recommendation: Merge

Executive Summary

Quarantine release now drops leftover attach proofs, so replacement drain can retry unadmitted messages; no remaining issues in the incremental fix.

Files Reviewed (2 files)

• services/cloud-agent-next/src/sandbox-session/session-message-queue.ts
• services/cloud-agent-next/src/sandbox-session/recovery/quarantine-releases-unadmitted-queue.test.ts

Previous review (commit eb9ca56)

Status: 1 Issue Found | Recommendation: Address before merge

Overview

Severity	Count
CRITICAL	0
WARNING	1
SUGGESTION	0

Issue Details (click to expand)

WARNING

File	Line	Issue
services/cloud-agent-next/src/sandbox-session/session-message-queue.ts	306	Release keeps dying-wrapper attach proofs, so replacement drain fails instead of retrying

Files Reviewed (4 files)

• services/cloud-agent-next/src/sandbox-session/session-message-queue.ts - 1 issue
• services/cloud-agent-next/src/sandbox-session/SandboxSession.ts - 0 issues
• services/cloud-agent-next/src/sandbox-session/recovery/quarantine-releases-unadmitted-queue.test.ts - 0 issues
• docs/plans/control-plane-not-ready-retry.md - 0 issues

Fix these issues in Kilo Cloud

---

_{Reviewed by grok-4.6 · Input: 114K · Output: 13K · Cached: 487.8K}

_{Review guidance: REVIEW.md from base branch eshurakov/recovery-stack}