fix: suppress session messages after close - #712

🤖 I have created a release *beep* *boop*
---


##
[2.6.0](v2.5.0...v2.6.0)
(2026-11-06)


### Features

* expose configured permission profiles as modes
([#395](#395))
([caf2e87](caf2e87))
* predict the follow-up prompt with thread/sample on the session thread
([#740](#740))
([f9cb470](f9cb470))
* show async Codex questions as elicitations
([#707](#707))
([cc57c7e](cc57c7e))
* update ACP SDK to 2.4 and align protocol behavior
([#727](#727))
([ab513aa](ab513aa))


### Bug Fixes

* clear stale entity metadata during ACP v2 replay
([#716](#716))
([580d8b9](580d8b9))
* defer startup interactions until session setup is delivered
([#714](#714))
([ad993bb](ad993bb))
* fence turn interrupt retries to the original prompt
([#723](#723))
([9c33f86](9c33f86))
* match vendor-prefixed gateway model ids such as OpenRouter's
([#731](#731))
([29195ec](29195ec))
* preserve sibling session metadata namespace fields
([#718](#718))
([3720341](3720341))
* publish complete configuration updates for session changes
([#715](#715))
([b7ac0bf](b7ac0bf))
* release the prompt suggestion thread and keep it minimal
([#709](#709))
([82ad58f](82ad58f))
* report verified standard subagent directories
([#722](#722))
([7d7e95a](7d7e95a))
* resynchronize current session metadata on ACP v2 resume
([#717](#717))
([927c480](927c480))
* scope authentication cancellation and initial status delivery
([#720](#720))
([e059ab7](e059ab7))
* show commands in Zed approval prompts
([#735](#735))
([cca2dca](cca2dca))
* skip the app-server restart when providers/set repeats the applied
config
([#728](#728))
([3b35338](3b35338))
* start the Codex app-server with the provider of the gateway routing
([#733](#733))
([cbcd446](cbcd446))
* suppress session messages after close
([#712](#712))
([85bf932](85bf932))
* synchronize resumed titles and reset replayed message metadata
([#713](#713))
([ef45a6d](ef45a6d))
* tear down session interactions and background processes on close
([#711](#711))
([1e89efa](1e89efa))
* update ACP SDK to 2.2 and align protocol behavior
([#710](#710))
([6f96fbe](6f96fbe))
* update codex to 0.166.0
([#734](#734))
([e53f23e](e53f23e))

---
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Co-authored-by: acp-release-bot[bot] <246668977+acp-release-bot[bot]@users.noreply.github.com>

Upstream v2.6.0 (agentclientprotocol#712, agentclientprotocol#718) publishes the archive state of an open session inside the archive's
delivery fence with publishAirSessionMetadata, because a closed session's delivery is sealed when
the fence ends and v2 composes the AIR namespace. The downstream update after the fence would now
be dropped. The archive state now goes through publishArchived inside the fence: AIR keeps
upstream's composed publication and a client-neutral ACP v1 opt-in gets _meta.sessionIndex.archived
as before. Upstream also moved the app-server initialize of initializeV2 before the capability
reads; the v2 session index still configures with neutral: false. A new test (AIR and neutral)
fails both without the neutral branch and with the publication after the fence.
Adapted from a1bfcc7 (original bf6dd64).